JP2021091896A - Polyethylene resin composition - Google Patents

Abstract

To provide a polyethylene resin composition which has excellent strength and fuse performance when be worked to a separator of a battery, can shorten time from start of fuse performance to completion of the fuse performance, and is less in film defects and film thickness unevenness.SOLUTION: A polyethylene resin composition has Mw of 100,000 or more and 1,000,000 or less and Mw/Mn of 2 or more and 18 or less. When an extract component obtained by temperature rise liberation fractionation according to a predetermined condition "temperature rise liberation fractionation of polyethylene resin composition" is measured by cross fractionation chromatography measurement according to a predetermined condition "CFC measurement condition of extract component" in a solution using o-dichlorobenzene as a solvent, an integral elution amount at 40°C or higher and lower than 90°C is 10 mass% or more and less than 70 mass% with respect to the total elution amount, an integral elution amount at 90°C or higher and 95°C or lower is 10 mass% or more with respect to the total elution amount, and a temperature at the maximum elution amount is 88°C or higher and 100°C or lower.SELECTED DRAWING: Figure 1

Description

The present invention relates to a polyethylene resin composition.

Polyethylene is used in various applications such as sheets, films, and molded products, and a raw material for a battery separator (hereinafter, may be referred to as a separator raw material) is one of the important applications.
The separator is a porous film used mainly for the purpose of separating the positive electrode and the negative electrode inside the battery and allowing only ions to permeate.
Other uses of the separator include use as a battery component for ensuring practically sufficient strength for the battery, and shutdown to prevent runaway of the battery reaction when the temperature inside the battery becomes high (hereinafter,). , Also referred to as a "fuse").

As the polyethylene as a raw material for the separator, polyethylene having a relatively high molecular weight and a high density is usually used as compared with general-purpose polyethylene used for sheets, films, molded products, etc., and the product is in powder form. Has been made.
The reason why polyethylene as a separator raw material has a high molecular weight and a high density is to ensure the strength of the separator.
The reason why polyethylene as a raw material for a separator is in a powder form is that it is difficult to pelletize it due to its poor processability due to its high molecular weight, and the powder form is more processable. Because it is better.

Much research and development has been carried out in order to obtain excellent separators. One of the issues is control of heat shrinkage in the film forming process.
Generally, the manufacturing process of a microporous membrane or the like includes a stretching step. Then, usually, after the stretching step, in order to suppress the heat shrinkage after stretching and the heat shrinkage under the use environment, annealing for relaxing the molecular orientation (hereinafter, may be described as "heat fixation"). .) The process is performed. In such a heat-fixing step, the molecular orientation is relaxed by the molecular motion of a component (hereinafter, may be referred to as “amorphous component”) that easily undergoes molecular motion even at a low temperature.
However, since high-density polyethylene having a high degree of crystallinity has a small proportion of the amorphous component, the molecular orientation may not be sufficiently relaxed even if the heat fixing step is performed, and the microporous membrane may not be sufficiently relaxed. There is a problem that the thickness or the like may not be stable due to heat shrinkage or the like.

As a method for solving such a problem, a method is known in which the average molecular weight and the molecular weight distribution of polyethylene are adjusted to ensure appropriate molecular motility in a low temperature state, and an annealing step (heat fixing step) is efficiently carried out. (See, for example, Patent Document 1).

In addition, if the average molecular weight of polyethylene is increased in order to increase the strength of the separator, the processability is deteriorated, which is a trade-off relationship, which is also mentioned as one of the problems to be considered as a main problem.
As a method for solving such a problem, by appropriately adjusting the average molecular weight and the molecular weight distribution of polyethylene, a molded product having excellent mechanical strength can be obtained, and excellent solubility or meltability can be ensured for processability. Is known (see, for example, Patent Document 2). Further, as a method for solving the same problem, a method of controlling the processing conditions of polyethylene powder (amount of solvent used, kneading temperature, kneading torque, etc.) is also known (see, for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 2014-118515 Japanese Unexamined Patent Publication No. 2014-118535 Japanese Unexamined Patent Publication No. 2010-235926

However, the techniques described in Patent Documents 1 to 3 have the effects of ensuring the strength of the film and controlling the heat shrinkage, but further have fuse performance, that is, a fuse under low temperature conditions. No studies have been made on improving the functions, shortening the time from the start of the fuse to the completion of the fuse, or achieving both of these functions. The demand for is increasing.

Therefore, in the present invention, when the separator is processed, it has excellent strength and fuse performance, the time from the start to the completion of the fuse is short, and the film defects and the uneven film thickness are reduced. It is an object of the present invention to provide a polyethylene resin composition which can be used.

As a result of intensive research to solve the above-mentioned problems of the prior art, the present inventor is a polyethylene resin composition having a predetermined weight average molecular weight and molecular weight distribution, and the polyethylene resin composition is released by increasing the temperature. When the extracted component obtained by fractionation is measured by cross fractional chromatography (hereinafter referred to as "CFC") under predetermined conditions using o-dichlorobenzene as a solvent, integrated elution at 40 ° C. or higher and lower than 90 ° C. The amount is an amount (mass%) in a predetermined range with respect to the total elution amount, and the integrated elution amount of 90 ° C. or higher and 95 ° C. or lower is a predetermined amount or more with respect to the total elution amount, and the maximum elution. We have found that the above problems can be solved by specifying the temperature to be a molecular weight within a predetermined temperature range, and have completed the present invention.
That is, the present invention is as follows.

[1]
The weight average molecular weight (Mw) is 100,000 or more and 1,000,000 or less.
A polyethylene resin composition having a molecular weight distribution (Mw / Mn) of 2 or more and 18 or less.
In a solution using o-dichlorobenzene as a solvent, which is an extract component obtained by temperature-increasing free fractionation according to "Temperature-increasing free fractionation condition of polyethylene resin composition" in the following (Condition 1), the following (Condition 1) When cross-separated chromatography measurement was performed according to "CFC measurement conditions for extracted components" in
The integrated elution amount of 40 ° C. or higher and lower than 90 ° C. is 10% by mass or more and less than 70% by mass of the total elution amount.
The integrated elution amount of 90 ° C. or higher and 95 ° C. or lower is 10% by mass or more of the total elution amount.
The temperature at which the maximum elution amount is 88 ° C or higher and 100 ° C or lower.
Polyethylene resin composition.
(Condition 1)
"Temperature rise free separation condition of polyethylene resin composition"
(1) Solvent; Toluene (2) Socksley extraction time; 6 hours (3) Method of collecting the extracted components extracted in the toluene solvent; Methanol is poured into the toluene solvent for reprecipitation, and the extracted components are suction-filtered. To get.
"CFC measurement conditions for extracted components"
(1) The o-dichlorobenzene solution of the extracted component is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the extract component is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (d) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 69 ° C. at 3 ° C. intervals.
(C) The temperature is raised from 69 ° C. to 100 ° C. at 1 ° C. intervals.
(D) The temperature is raised from 100 ° C. to 120 ° C. at 10 ° C. intervals.
[2]
The comonomer content when the extracted component obtained by temperature-increasing free separation of the polyethylene resin composition according to the "temperature-increasing free separation condition of the polyethylene resin composition" in (Condition 1) was measured by 13C-NMR. The polyethylene resin composition according to the above [1], wherein is 0.01 mol% or more and 5 mol% or less.
[3]
The melting point of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 125 ° C. or higher and 135 ° C. or lower. , The polyethylene resin composition according to the above [1] or [2].
[4]
The lamella thickness of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 6 nm or more and 14 nm or less. The polyethylene resin composition according to any one of the above [1] to [3].
[5]
The lamella thickness of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is determined.
The polyethylene resin composition according to any one of the above [1] to [4], which is 10 nm or more and 14 nm or less.
[6]
The weight average molecular weight (Mw) of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 20,000. The polyethylene resin composition according to any one of [1] to [5] above, wherein the polyethylene resin composition is 350,000 or less and the molecular weight distribution (Mw / Mn) is 2 or more and 14 or less.
[7]
A solution using о-dichlorobenzene as a solvent, which is an extract component obtained by separating the polyethylene resin composition by increasing the temperature according to the “conditions for separating the polyethylene resin composition by increasing the temperature” in the above (Condition 1). In CFC measurement according to the above-mentioned (Condition 1) "CFC measurement condition of extracted component",
The polyethylene resin composition according to any one of [1] to [6] above, wherein the temperature at which the integrated elution amount reaches 10% by mass of the total elution amount is 70 ° C. or higher and 90 ° C. or lower.
[8]
The Ti content of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 5 ppm or less. 1] The polyethylene resin composition according to any one of [7].
[9]
The Al content of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 10 ppm or less. 1] The polyethylene resin composition according to any one of [8].
[10]
In a solution using o-dichlorobenzene of the polyethylene resin composition as a solvent, when CFC measurement was performed in accordance with the following conditions (Condition 2),
The integrated elution amount of 40 ° C. or higher and lower than 95 ° C. is 15% by mass or more and 70% by mass or less of the total elution amount.
The integrated elution amount of 95 ° C. or higher and 105 ° C. or lower is 15% by mass or more of the total elution amount.
It has at least two or more elution peaks, and the temperature at which the maximum elution amount is 88 ° C. or higher and 100 ° C. or lower.
The polyethylene resin composition according to any one of the above [1] to [9].
(Condition 2)
(1) The o-dichlorobenzene solution of the polyethylene resin composition is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the polyethylene resin composition is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (e) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 75 ° C. at 5 ° C. intervals.
(C) The temperature is raised from 75 ° C. to 90 ° C. at 3 ° C. intervals.
(D) The temperature is raised from 90 ° C. to 110 ° C. at 1 ° C. intervals.
(E) The temperature is raised from 110 ° C. to 120 ° C. at 5 ° C. intervals.
[11]
The polyethylene resin composition according to any one of the above [1] to [10], wherein the Ti content of the polyethylene resin composition is 5 ppm or less.
[12]
The polyethylene resin composition according to any one of the above [1] to [11], wherein the Al content of the polyethylene resin composition is 10 ppm or less.

According to the present invention, when processed into a battery separator, it has excellent strength and fuse performance, and it is possible to shorten the time from the start to the completion of the fuse, and further, film defects and uneven film thickness. A polyethylene resin composition with a small amount of water can be obtained.

The image figure of the measurement result in the cross-separation chromatography measurement is shown.

Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail. It should be noted that the present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following contents. The present invention can be implemented with various modifications within the scope of the gist thereof.

In the present specification, the term "fuse performance" refers to, for example, when the separator is processed, the temperature rises in an abnormal state (such as thermal runaway of a battery), the polymer melts, the micropores are closed, and ion conduction occurs. A function that allows the battery to be used safely by shutting it down. When this fuse performance functions, the charge / discharge function is lost, so that the risk of thermal runaway of the battery is reduced.

[Polyethylene resin composition]
The polyethylene resin composition of the present embodiment is
A polyethylene resin composition having a weight average molecular weight (Mw) of 100,000 or more and 1,000,000 or less and a molecular weight distribution (Mw / Mn) of 2.0 or more and 18.0 or less, as follows (Condition 1). ) In the solution using o-dichlorobenzene as a solvent of the extraction component obtained by the temperature increase free fractionation according to the "temperature increase free fractionation condition of the polyethylene resin composition" in the following (condition 1) "extraction component". When measured by cross fractionation chromatography (hereinafter referred to as "CFC") according to "CFC measurement conditions", the integrated elution amount of 40 ° C. or higher and lower than 90 ° C. is 10% by mass or more and less than 70% by mass of the total elution amount. A polyethylene resin composition having an integrated elution amount of 90 ° C. or higher and 95 ° C. or lower, which is 10% by mass or more of the total elution amount, and a temperature at which the maximum elution amount is 88 ° C. or higher and 100 ° C. or lower. ..
(Condition 1)
"Temperature rise free separation condition of polyethylene resin composition"
(1) Solvent; Toluene (2) Socksley extraction time; 6 hours (3) Method of collecting the extracted components extracted in the toluene solvent; Methanol is poured into the toluene solvent for reprecipitation, and the extracted components are suction-filtered. To get.
"CFC measurement conditions for extracted components"
(1) The o-dichlorobenzene solution of the extracted component is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the extract component is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (d) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 69 ° C. at 3 ° C. intervals.
(C) The temperature is raised from 69 ° C. to 100 ° C. at 1 ° C. intervals.
(D) The temperature is raised from 100 ° C. to 120 ° C. at 10 ° C. intervals.
The above requirements will be described below.

The polyethylene resin composition of the present embodiment contains an ethylene polymer (hereinafter, also referred to as "polyethylene").
Examples of the ethylene-based polymer include an ethylene homopolymer and a copolymer of ethylene and another comonomer copolymerizable with the ethylene (for example, a binary or ternary copolymer). The bonding form of the copolymer may be random or block.
The other comonomer is not particularly limited, and examples thereof include α-olefins and vinyl compounds.
As the other comonomer, one type may be used alone, or two or more types may be used in combination.
The α-olefin is not particularly limited, and examples thereof include α-olefins having 3 to 20 carbon atoms, and specific examples thereof include propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-hexene. -Ocene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene and the like can be mentioned. Among these, the other comonomer is preferably propylene and / or 1-butene from the viewpoint of further improving the heat resistance and strength of the molded product such as the film and the fiber.
The vinyl compound is not particularly limited, and examples thereof include vinylcyclohexane, styrene, and derivatives thereof.
Further, as another comonomer, non-conjugated polyenes such as 1,5-hexadiene and 1,7-octadiene may be used, if necessary.

The polyethylene resin composition of the present embodiment can also be used in the form of a mixture in which ethylene-based polymers having different weight average molecular weights, molecular weight distributions, etc. are mixed (blended), and low-density polyethylene, linear low-density polyethylene, polypropylene, etc. It can also be used in the form of a mixture mixed (blended) with various resins such as polypropylene. Further, it may be obtained by multi-stage polymerization. Further, it may be a molded product obtained by molding the mixture. Furthermore, it may be a mixture of an ethylene polymer and an additive such as an antioxidant.

(Weight average molecular weight (Mw) of polyethylene resin composition)
The weight average molecular weight (Mw) of the polyethylene resin composition of the present embodiment is 100,000 or more and 1,000,000 or less, preferably 120,000 or more and 800,000 or less, and more preferably 140,000 or more. It is 600,000 or less.
The Mw of the polyethylene resin composition can be controlled within the above numerical range by appropriately adjusting the polymerization conditions and the like using a catalyst described later. Specifically, the weight average molecular weight (Mw) can be controlled by allowing hydrogen to exist in the polymerization system, changing the polymerization temperature, or the like. Further, by adding hydrogen as a chain transfer agent into the polymerization system, the molecular weight can be controlled in an appropriate range.

When the weight average molecular weight (Mw) is 100,000 or more, the strength can be improved. On the other hand, when the weight average molecular weight (Mw) is 1,000,000 or less, melt fluidity, dissolution in a solvent, stretching, etc. are facilitated, so that workability is improved, and film defects and film thickness unevenness are improved. Can be reduced.

(Molecular weight distribution of polyethylene resin composition (Mw / Mn))
The molecular weight distribution (Mw / Mn) of the polyethylene resin composition of the present embodiment is 2.0 or more and 18.0 or less, preferably 4.0 or more and 18.0 or less, and more preferably 6.0 or more and 17 It is less than or equal to 0.0.
In the polyethylene resin composition of the present embodiment, the molecular weight distribution of the polyethylene resin composition is reduced by using a catalyst, keeping the conditions (hydrogen concentration, temperature, ethylene pressure, etc.) in the polymerization system constant, and the like. can do. Therefore, it is preferable to polymerize in a continuous manner. On the other hand, as a method for increasing the molecular weight distribution of the polyethylene resin composition, for example, a method of changing the conditions during polymerization by batch polymerization (for example, a method of changing the concentration of hydrogen which is a chain transfer agent during polymerization). Alternatively, a method of intermittently introducing a catalyst by batch polymerization or the like can be mentioned.

When the molecular weight distribution (Mw / Mn) is 2.0 or more, the polyethylene resin composition of the present embodiment has more excellent molding processability, and as a result, it is used for stretch molded articles, microporous membranes, and batteries. The separator will have excellent strength. On the other hand, when the molecular weight distribution (Mw / Mn) is 18.0 or less, the molecular chain length becomes uniform and more excellent strength can be obtained.

The number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the polyethylene resin composition of the present embodiment are determined by gel permeation chromatography of an o-dichlorobenzene solution in which an ethylene polymer is dissolved. Hereinafter, it can also be obtained by measuring with "GPC") and based on a molecular weight line prepared by using a commercially available monodisperse polystyrene. More specifically, it can be measured by the method described in Examples described later.

(Extracted components obtained by free-separating the polyethylene resin composition by increasing temperature)
The extraction component obtained by subjecting the polyethylene resin composition of the present embodiment to temperature-increasing free separation according to the above-mentioned (Condition 1) "Temperature-increasing free separation condition" is extracted from the above-mentioned (Condition 1). The integrated elution amount of 40 ° C. or more and less than 90 ° C. when measured by CFC according to "CFC measurement conditions of components" is 10% by mass or more and less than 70% by mass, preferably 15% by mass or more and 65% by mass or less of the total elution amount. It is more preferably 20% by mass or more and 60% by mass or less, and further preferably 30% by mass or more and 60% by mass or less.
The integrated elution amount of 90 ° C. or higher and 95 ° C. or lower is 10% by mass or more, preferably 13% by mass or more, and more preferably 15% by mass or more of the total elution amount.
The temperature at which the maximum elution amount is obtained is 88 ° C. or higher and 100 ° C. or lower, preferably 90 ° C. or higher and 97 ° C. or lower, and more preferably 92 ° C. or higher and 95 ° C. or lower.
FIG. 1 shows an image diagram showing the relationship between the temperature and the elution amount in the CFC measurement.
The extracted component obtained by separating the polyethylene resin composition of the present embodiment by increasing the temperature according to the above-mentioned "conditions for separating the polyethylene resin composition by increasing the temperature" is the polyethylene resin composition of the present embodiment. It is the most effective component (component that causes fuse) in improving the fuse performance of the fine pore film. The integrated elution amount of 40 ° C. or higher and lower than 90 ° C. is 10% by mass or more and less than 70% by mass of the total elution amount, and the integrated elution amount of 90 ° C. or higher and 95 ° C. or lower is 10% by mass of the total elution amount. As described above, when the temperature at which the maximum elution amount is 88 ° C. or higher and 95 ° C. or lower, the component (A) eluted at a low temperature of 40 ° C. or higher and lower than 90 ° C. can start flowing in the fine pore membrane. The component (B) eluted at 90 ° C. or higher and 95 ° C. or lower can moderately relax the rigidity of the component forming the pores of the fine pore membrane, so that the time until the pores are closed can be shortened. That is, it is possible to simultaneously improve the fuse performance and shorten the time from the start of the fuse to the completion (hereinafter, also referred to as "fuse speed").
Further, it is preferable that this extracted component exhibits an elution behavior in which the elution amount gradually increases as the temperature rises in a temperature range of 40 ° C. or higher and lower than 90 ° C. The gradual elution means that in the step of swelling and dissolving the polyethylene resin composition with liquid paraffin, the time required for the component corresponding to the extracted component in the polyethylene resin composition to swell can be slowed down. , There is a tendency that the possibility that unmelted components aggregate with each other due to poor swelling of the polyethylene resin composition and become a defect can be reduced.

The integrated elution amount of 40 ° C. or higher and lower than 90 ° C. when the extracted component obtained by free-separating the polyethylene resin composition of the present embodiment by temperature rise is measured by CFC is 10% by mass or more and 70% by mass of the total elution amount. In order to control the integrated elution amount of 90 ° C. or higher and 95 ° C. or lower to 30% by mass or more of the total elution amount and the temperature at which the maximum elution amount is 88 ° C. or higher and 95 ° C. or lower, a polyethylene resin composition is used. It is important to control the method for producing the polyethylene-based polymer contained.
That is, as a method for producing the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment, a method of initiating polymerization on the active site of the catalyst in an environment where the surrounding catalyst concentration is low and the like can be mentioned. For example, a method of preventing the polymerization reaction and catalyst activation from occurring for a short time immediately after the catalyst feed can be mentioned. Specifically, the temperature of the catalyst to be charged into the reactor is adjusted to less than 5 ° C. to prevent the catalyst. The feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. For example, it is introduced into the inside, and the remaining ethylene is introduced from the ethylene feed port. Further, a method of diffusing the catalyst before it comes into contact with ethylene for the first time can be mentioned. More specifically, the catalyst and ethylene-dissolved hexane are introduced into the reactor from a plurality of places, and the feed rate of the catalyst is 3.0 m. Controlling to / s or more and 5.0 m / s or less can be mentioned.

Here, the "cross fractionation chromatography (CFC)" is an apparatus that combines a temperature-increasing elution fractionation section (hereinafter, also referred to as "TREF section") that performs crystalline fractionation and a GPC section that performs molecular weight fractionation. By directly connecting the TREF unit and the GPC unit, it is possible to analyze the interrelationship between the composition distribution and the molecular weight distribution. The measurement in the TREF unit may be referred to as the measurement in the CFC.

The measurement by the TREF unit is performed as follows based on the principle described in "Journal of Applied Polymer Science, Vol 26, 4217-4231 (1981)".
The ethylene polymer to be measured is completely dissolved in o-dichlorobenzene. Then, it is cooled at a constant temperature to form a thin polymer layer on the surface of the inert carrier. At this time, the component having high crystallinity is crystallized first, and then the component having low crystallinity is crystallized as the temperature decreases. Next, when the temperature is raised stepwise, the components having low crystallinity are eluted in order from the components having high crystallinity, and the concentration of the eluted components at a predetermined temperature can be detected.

The elution amount and the elution integral amount at each temperature of the extracted components obtained by free fractionation by increasing the temperature from the polyethylene resin composition are determined by measuring the elution temperature-elution amount curve as follows by the TREF unit. be able to.
Specifically, first, the column containing the filler is heated to 140 ° C., and the extraction component obtained by free fractionation by increasing the temperature from the polyethylene resin composition is dissolved in o-dichlorobenzene (for example,). Concentration: 20 mg / 20 mL) is introduced and held for 120 minutes.

Next, the temperature is lowered to 40 ° C. at a temperature lowering rate of 0.5 ° C./min and then held for 20 minutes to precipitate the sample on the filler surface. After that, the temperature of the column is sequentially raised at a heating rate of 20 ° C./min. The temperature is raised from 40 ° C to 60 ° C at 10 ° C intervals, from 60 ° C to 69 ° C at 3 ° C intervals, from 69 ° C to 100 ° C at 1 ° C intervals, and from 100 ° C to 120 ° C. The temperature is raised at intervals of 10 ° C. After holding the sample at each temperature reached for 21 minutes, the temperature is raised to detect the concentration of the sample eluted at each temperature. Then, the elution temperature-elution amount curve is measured from the values of the elution amount (mass%) of the sample and the in-column temperature (° C.) at that time, and the elution amount and the elution integral amount at each temperature are obtained. More specifically, it can be measured by the method described in Examples described later.

(Temperature rise free separation)
Here, the temperature rise free fractionation is a method of dissolving and extracting a target component soluble in a solvent from a sample using a solvent using a general Soxhlet extractor.
A Soxhlet extractor is a device with a heater and a container containing a solvent at the bottom, a cylinder containing a filter paper containing a sample in the middle, and a cooling tube at the top. When the container containing the solvent is heated, the solvent evaporates, is cooled by the uppermost cooling tube, drips into the sample, dissolves a small amount of the solvent-soluble component, and then returns to the container containing the solvent. Since the solvent-soluble component has a higher boiling point than the solvent, by repeating this cycle, the solvent-soluble component (extracted component) is gradually concentrated in the container containing the solvent, and the solvent-insoluble component (residual) is contained in the filter paper. Things) remain. As the solvent, toluene, xylene and the like are generally mentioned, but in the present embodiment, toluene is used as described in the above (condition 1).

(Comonomer content of extracted components)
The comonomer content of the extracted component obtained by separating the polyethylene resin composition of the present embodiment by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is preferably 0. It is 0.01 mol% or more and 5 mol% or less, more preferably 0.05 mol% or more and 3 mol% or less, and further preferably 0.1 mol% or more and 2 mol% or less.
When the comonomer content is 0.01 mol% or more, the fuse performance is excellent, and when it is 5 mol% or less, the fuse speed can be further increased. As a result, when the polyethylene resin composition of the present embodiment is processed into a fine pore film, the temperature rises in an abnormal situation (such as thermal runaway of a battery), the polymer melts, the fine pores are closed, and ion conduction is shut down. By doing so, the charge / discharge function is lost, and the risk of thermal runaway of the battery can be reduced.
The comonomer content of the extracted component can be measured by 13C-NMR, and specifically, by the method described in Examples described later.
<Achievement means>
As a method for controlling the comonomer content of the extract component obtained by free separation by increasing the temperature from the polyethylene resin composition of the present embodiment to 0.01 mol% or more and 5 mol% or less, an environment in which the ambient catalyst concentration is low Examples thereof include a method of initiating polymerization on the active point of the catalyst. For example, a method of preventing the polymerization reaction and catalyst activation from occurring for a short time immediately after the catalyst feed can be mentioned. Specifically, the temperature of the catalyst to be charged into the reactor is adjusted to less than 5 ° C. to prevent the catalyst. The feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. For example, it is introduced into the inside, and the remaining ethylene is introduced from the ethylene feed port. Another method is to diffuse the catalyst before it comes into contact with ethylene for the first time. Specifically, the catalyst and ethylene-dissolved hexane are introduced into the reactor from multiple locations, and the feed rate of the catalyst is 3.0 m /. Controlling to s or more and 5.0 m / s or less can be mentioned.
Further, a method of adjusting the amount of comonomer added can be mentioned.

(Melting point of extracted components)
The melting point of the extracted component obtained from the polyethylene resin composition of the present embodiment by temperature-increasing free separation according to the "temperature-increasing free separation condition of the polyethylene resin composition" in (Condition 1) described above is preferably 125 ° C. It is 135 ° C. or higher, more preferably 125 ° C. or higher and 132 ° C. or lower, and further preferably 125 ° C. or higher and 130 ° C. or lower.
Since the melting point of the extracted component is 125 ° C. or higher, the fuse performance is excellent, and heat fixation can be performed without blocking the pores of the fine pore membrane of the polyethylene resin composition of the present embodiment, and at 135 ° C. or lower. By being there, the fuse speed can be increased. As a result, when the polyethylene resin composition of the present embodiment is processed into a fine pore film, the temperature rises at an abnormal time (such as thermal runaway of a battery), the polymer melts, the pores are closed, and ion conduction is shut down. By doing so, the charge / discharge function is lost, and the risk of thermal runaway of the battery can be reduced. The melting point of the extracted component can be measured by the method described in Examples described later.
<Achievement means>
As a method of controlling the melting point of the extracted component obtained by temperature-increasing free separation from the polyethylene resin composition of the present embodiment to 125 ° C. or higher and 135 ° C. or lower, the active site of the catalyst is used in an environment where the ambient catalyst concentration is low. Examples thereof include a method of initiating the polymerization in. For example, a method of preventing the polymerization reaction and catalyst activation from occurring for a short time immediately after the catalyst feed can be mentioned. Specifically, the temperature of the catalyst to be charged into the reactor is adjusted to less than 5 ° C. to prevent the catalyst. The feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. For example, it is introduced into the inside, and the remaining ethylene is introduced from the ethylene feed port. Another method is to diffuse the catalyst before it comes into contact with ethylene for the first time. Specifically, the catalyst and ethylene-dissolved hexane are introduced into the reactor from multiple locations, and the feed rate of the catalyst is 3.0 m /. Controlling to s or more and 5.0 m / s or less can be mentioned.

(Lamera thickness of extracted ingredients)
The lamella thickness of the extracted component obtained by separating the polyethylene resin composition of the present embodiment by increasing the temperature according to the above-mentioned "conditions for separating the polyethylene resin composition by increasing the temperature" is preferably 6 nm or more and 14 nm. It is less than or equal to, more preferably 8 nm or more and 14 nm or less, and further preferably 10 nm or more and 14 nm or less.
When the lamella thickness is 6 nm or more, the fuse performance is excellent, and when it is 14 nm or less, the fuse speed can be further increased. As a result, when the polyethylene resin composition of the present embodiment is processed into a fine pore film, the temperature rises in an abnormal situation (such as thermal runaway of a battery), the polymer melts, the fine pores are closed, and ion conduction is shut down. By doing so, the charge / discharge function is lost, and the risk of thermal runaway of the battery can be reduced. The lamella thickness of the extracted component can be measured by the method described in Examples described later.
<Achievement means>
As a method for controlling the lamella thickness of the extracted component obtained by free separation by increasing the temperature from the polyethylene resin composition of the present embodiment to 6 nm or more and 14 nm or less, preferably 10 nm or more and 14 nm or less, an environment in which the ambient catalyst concentration is low Examples thereof include a method of initiating polymerization on the active site of the catalyst. For example, a method of preventing the polymerization reaction and catalyst activation from occurring for a short time immediately after the catalyst feed can be mentioned. Specifically, the temperature of the catalyst to be charged into the reactor is adjusted to less than 5 ° C. to prevent the catalyst. The feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. For example, it is introduced into the inside, and the remaining ethylene is introduced from the ethylene feed port. Another method is to diffuse the catalyst before it comes into contact with ethylene for the first time. Specifically, the catalyst and ethylene-dissolved hexane are introduced into the reactor from multiple locations, and the feed rate of the catalyst is 3.0 m /. Controlling to s or more and 5.0 m / s or less can be mentioned.

(Weight average molecular weight (Mw) of extracted components)
The weight average molecular weight (Mw) of the extracted component obtained by separating the polyethylene resin composition of the present embodiment by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is determined. It is preferably 20,000 or more and 350,000 or less, more preferably 50,000 or more and 300,000 or less, and further preferably 70,000 or more and 250,000 or less.
The Mw of the extract component can be controlled within the above numerical range by appropriately adjusting the polymerization conditions and the like using a catalyst described later. Specifically, the weight average molecular weight (Mw) of the extracted component can be controlled by allowing hydrogen to exist in the polymerization system of the ethylene-based polymer, changing the polymerization temperature, or the like. By adding hydrogen as a chain transfer agent into the polymerization system, the weight average molecular weight can be controlled in an appropriate range.

When the weight average molecular weight (Mw) of the extracted component is 20,000 or more, the strength can be further improved. On the other hand, when the weight average molecular weight (Mw) of the extracted component is 350,000 or less, melt fluidity, dissolution in a solvent, stretching, etc. are facilitated, and processability is improved.

(Molecular weight distribution of extracted components (Mw / Mn)
The molecular weight distribution (Mw / Mn) of the extracted components obtained by subjecting the polyethylene resin composition of the present embodiment to temperature-increasing free fractionation according to the "temperature-increasing free fractionation condition of the polyethylene resin composition" in the above (Condition 1) is It is preferably 2.0 or more and 14.0 or less, more preferably 4.0 or more and 13.0 or less, and further preferably 6.0 or more and 12.0 or less. The molecular weight distribution of the extracted components can be reduced by using a catalyst described later in the polymerization step of the ethylene polymer or by keeping the conditions (hydrogen concentration, temperature, ethylene pressure, etc.) in the polymerization system constant. .. Therefore, it is preferable to polymerize in a continuous manner. On the other hand, as a method for increasing the molecular weight distribution of the extracted component, a method of changing the conditions during polymerization by batch polymerization (for example, a method of changing the concentration of hydrogen as a chain transfer agent during polymerization), a batch method, etc. Examples thereof include a method of intermittently introducing a catalyst by polymerization.

When the molecular weight distribution (Mw / Mn) of the extracted components is 2.0 or more, the polyethylene resin composition of the present embodiment has more excellent molding processability, and as a result, the stretched molded product, the microporous film, and the like. And the battery separator will have excellent dimensional accuracy and strength. On the other hand, when the molecular weight distribution (Mw / Mn) of the extracted components is 14.0 or less, the molecular chain length becomes uniform, so that more excellent strength can be obtained.

(Temperature at which the integrated elution amount when CFC measurement of the extracted components reaches 10% by mass of the total elution amount)
The extracted component obtained by subjecting the polyethylene resin composition of the present embodiment to temperature-increasing free fractionation according to the "temperature-increasing free fractionation condition of the polyethylene resin composition" in the above-mentioned (Condition 1) is obtained from the above-mentioned (Condition 1) "Condition 1". The temperature at which the integrated elution amount reaches 10% by mass of the total elution amount when measured by CFC according to "CFC measurement conditions of extracted components" is preferably 70 ° C. or higher and 90 ° C. or lower, and more preferably 72 ° C. or higher and 90 ° C. The temperature is as follows, more preferably 75 ° C. or higher and 90 ° C.
Since the temperature at which the integrated elution amount reaches 10% by mass of the total elution amount when measured by CFC is in the low temperature region of 70 ° C. or higher and 90 ° C. or lower, the fuse performance can be improved and the fuse speed can be increased. it can. As a result, when processed into a fine pore film, the temperature rises in an abnormal situation (such as thermal runaway of a battery), the polymer melts, the fine pores are blocked, and ion conduction shuts down, resulting in loss of charge / discharge function. However, the risk of thermal runaway of the battery can be reduced.
<Achievement means>
The temperature at which the integrated elution amount when the extracted component obtained by free fractionation by increasing the temperature from the polyethylene resin composition of the present embodiment is measured by CFC is 70 ° C. or higher and 90 ° C. or lower to reach 10% by mass of the total elution amount. Examples of the method of controlling the above include a method of initiating polymerization on the active point of the catalyst in an environment where the concentration of the catalyst is low in the surroundings. For example, a method of preventing the polymerization reaction and catalyst activation from occurring for a short time immediately after the catalyst feed can be mentioned. Specifically, the temperature of the catalyst to be charged into the reactor is adjusted to less than 5 ° C. to prevent the catalyst. The feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. For example, it is introduced into the inside, and the remaining ethylene is introduced from the ethylene feed port. Another method is to diffuse the catalyst before it comes into contact with ethylene for the first time. Specifically, the catalyst and ethylene-dissolved hexane are introduced into the reactor from multiple locations, and the feed rate of the catalyst is 3.0 m /. Controlling to s or more and 5.0 m / s or less can be mentioned.

(Ti and Al content of extracted components)
The titanium (Ti) content of the extracted component obtained by separating the polyethylene resin composition of the present embodiment by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is determined. It is preferably 5 ppm or less, more preferably 4 ppm or less, and further preferably 3 ppm or less. The aluminum (Al) content is preferably 10 ppm or less, more preferably 8 ppm or less, still more preferably 6 ppm or less.
By controlling the amount of metal in this way, the reaction with the antioxidant and the heat stabilizer can be suppressed, and the coloring of the molded product due to the formation of the organometallic complex tends to be suppressed. Further, by controlling the amount of metal in the extracted component, it tends to be possible to obtain a yarn having a uniform yarn diameter when it is made into a fiber and a film having a uniform film thickness when it is made into a film.
The contents of Ti and Al in the extraction component can be controlled by the productivity of the ethylene polymer per unit catalyst. The productivity of the ethylene-based polymer can be controlled by the polymerization temperature, polymerization pressure, and slurry concentration of the reactor at the time of production. Other methods include selecting the type of co-catalyst component when polymerizing the ethylene-based polymer, lowering the concentration of the co-catalyst component, and washing the ethylene-based polymer with an acid or alkali. The amount can be controlled. In this embodiment, the amounts of Ti and Al can be measured by the method described in Examples described later.

(Cross fractional chromatography (CFC) measurement of polyethylene resin composition)
In the solution of the polyethylene resin composition of the present embodiment using о-dichlorobenzene as a solvent, the integrated elution amount of 40 ° C. or higher and lower than 95 ° C. measured by CFC in accordance with the following <Condition 2> is preferably total. The elution amount is 15% by mass or more and 70% by mass or less, more preferably 25% by mass or more and 70% by mass or less, and further preferably 35% by mass or more and 65% by mass or less.
The integrated elution amount of 95 ° C. or higher and 105 ° C. or lower is preferably 15% by mass or more, more preferably 20% by mass or more, and further preferably 25% by mass or more of the total elution amount.
Further, it is preferable to have at least two or more peaks, and the temperature at which the maximum elution amount is reached is preferably 88 ° C. or higher and 100 ° C. or lower, and more preferably 88 ° C. or higher and 95 ° C. or lower.
<Condition 2>
(1) The o-dichlorobenzene solution of the polyethylene resin composition is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the polyethylene resin composition is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (e) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 75 ° C. at 5 ° C. intervals.
(C) The temperature is raised from 75 ° C. to 90 ° C. at 3 ° C. intervals.
(D) The temperature is raised from 90 ° C. to 110 ° C. at 1 ° C. intervals.
(E) The temperature is raised from 110 ° C. to 120 ° C. at 5 ° C. intervals.

The integrated elution amount of 40 ° C. or higher and lower than 95 ° C. measured by CFC is 15% by mass or more and 70% by mass or less of the total elution amount, and the integrated elution amount of 95 ° C. or higher and 105 ° C. or lower is 15% by mass or more of the total elution amount. By having at least two peaks and a temperature at which the maximum elution amount is 88 ° C. or higher and 100 ° C. or lower, the fuse performance and the fuse speed can be further improved, and even after the micropores are closed. Since the film shape can be maintained, short circuits between the electrodes can be prevented, the safety of the battery can be further improved, and the strength of the film itself tends to be further improved.

In a solution using о-dichlorobenzene of the polyethylene resin composition of the present embodiment as a solvent, when CFC measurement was performed in accordance with the above (Condition 2), the integrated elution amount of 40 ° C. or higher and lower than 95 ° C. was the total elution amount. The integrated elution amount of 15% by mass or more and 70% by mass or less and 95 ° C. or more and 105 ° C. or less is 15% by mass or more of the total elution amount, has at least two elution peaks, and has a temperature at which the maximum elution amount is 88. As a method of controlling the temperature to 100 ° C. or higher, the temperature of the catalyst charged into the reactor is adjusted to less than 5 ° C. in producing the ethylene-based polymer contained in the polyethylene resin composition of the present embodiment. Then, the catalyst feed port, the ethylene feed port, and the hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor and all are introduced into the reactor at the same time. The remaining ethylene is introduced from the ethylene feed port, and the catalyst feed port, ethylene feed port, and hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all are introduced into the reactor at the same time. As an effective method, when the solid catalyst and the co-catalyst are charged into the reactor, they are charged alternately in an intermittent manner and the two are brought into contact with each other at the moment when they are charged into the reactor.

The elution amount and the elution integral amount at each temperature of the polyethylene resin composition can be obtained by measuring the elution temperature-elution amount curve from the TREF unit as follows. Specifically, first, the temperature of the column containing the filler is raised to 140 ° C., and a sample solution (for example, concentration: 20 mg / 20 mL) in which the polyethylene resin composition is dissolved in o-dichlorobenzene is introduced for 120 minutes. Hold.

Next, the temperature is lowered to 40 ° C. at a temperature lowering rate of 0.5 ° C./min and then held for 20 minutes to precipitate the sample on the filler surface. After that, the temperature of the column is sequentially raised at a heating rate of 20 ° C./min. The temperature rises from 40 ° C to 60 ° C at 10 ° C intervals, from 60 ° C to 75 ° C at 5 ° C intervals, from 75 ° C to 90 ° C at 3 ° C intervals, and from 90 ° C to 110 ° C. The temperature is raised at 1 ° C. intervals, and from 110 ° C. to 120 ° C. at 5 ° C. intervals. After holding the sample at each temperature for 21 minutes, the temperature is raised to detect the concentration of the sample eluted at each temperature. Then, the elution temperature-elution amount curve is measured from the values of the elution amount (mass%) of the sample and the in-column temperature (° C.) at that time, and the elution amount and the elution integral amount at each temperature can be obtained. More specifically, it can be measured by the method described in Examples described later.

(Ti, Al content of polyethylene resin composition)
The titanium (Ti) content of the polyethylene resin composition of the present embodiment is preferably 5 ppm or less, more preferably 4 ppm or less, and further preferably 3 ppm or less. The aluminum (Al) content is preferably 10 ppm or less, more preferably 8 ppm or less, still more preferably 6 ppm or less.
By adjusting the amount of metal in this way, the reaction with the antioxidant and the heat stabilizer can be suppressed, and the coloring of the molded product due to the formation of the organometallic complex tends to be suppressed. Further, by adjusting the amount of metal in the polyethylene resin composition, it is possible to obtain a yarn having a uniform yarn diameter when it is made into a fiber and a film having a uniform film thickness when it is made into a film.
The contents of Ti and Al in the polyethylene resin composition can be controlled by the productivity of the ethylene polymer per unit catalyst. The productivity of the ethylene-based polymer can be controlled by the polymerization temperature, polymerization pressure, and slurry concentration of the reactor at the time of production. Other methods include selecting the type of co-catalyst component when polymerizing the ethylene-based polymer, lowering the concentration of the co-catalyst component, and washing the ethylene-based polymer with an acid or alkali. It is possible to control the amount. In this embodiment, the amounts of Ti and Al can be measured by the method described in Examples described later.

[Method for producing ethylene polymer contained in the polyethylene resin composition of the present embodiment]
(Catalyst component)
The polyethylene resin composition of the present embodiment contains a polyethylene-based polymer.
The polyethylene-based polymer can be produced by performing a polymerization step in the presence of a predetermined catalyst.
The catalyst component is not particularly limited, and examples thereof include general Ziegler-Natta catalysts and metallocene catalysts.

<Ziegler-Natta catalyst>
The Ziegler-Natta catalyst is a catalyst composed of a solid catalyst component [A] and an organic metal compound component [B], and the solid catalyst component [A] is an inert hydrocarbon solvent represented by the following (formula 1). A catalyst for olefin polymerization produced by reacting an organic magnesium compound (A-1) soluble in water with a titanium compound (A-2) represented by the following (formula 2) is preferable.
(A-1): (M ¹ ) α (Mg) β (R ² ) _a (R ³ ) _b (Y ¹ ) _c ... (Equation 1)
(In Equation 1, M ¹ is a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table, and R ² and R ³ are hydrocarbon groups having 2 to 20 carbon atoms. , Y ¹ is alkoxy, siloxy, allyloxy, amino, amide, -N = C-R ⁴ , R ⁵ , -SR ⁶ (where R ⁴ , R ⁵ and R ⁶ are hydrocarbons with 1 or more and 20 or less carbon atoms. Represents a group. When c is 2, Y ¹ may be different), β-ketoic acid residue, and α, β, a, b and c have the following relationship. It is a real number to be satisfied. 0 ≦ α, 0 <β, 0 ≦ a, 0 ≦ b, 0 ≦ c, 0 <a + b, 0 ≦ c / (α + β) ≦ 2, nα + 2β = a + b + c (where n is M ¹ Represents the valence of.)))

(A-2): Ti (OR ⁷ ) _d X ¹ _(4-d) ... (Equation 2)
(In Equation 2, d is a real number of 0 or more and 4 or less, R ⁷ is a hydrocarbon group having 1 or more carbon atoms and 20 or less, and X ¹ is a halogen atom.)

The inert hydrocarbon solvent used for the reaction between the organic magnesium compound (A-1) and the titanium compound (A-2) is not particularly limited, but for example, an aliphatic hydrocarbon such as pentane, hexane, and heptane. Aromatic hydrocarbons such as benzene and toluene; and alicyclic hydrocarbons such as cyclohexane and methylcyclohexane can be mentioned.

First, the organic magnesium compound (A-1) will be described.
The (A-1) is shown as a complex compound of organic magnesium soluble in an inert hydrocarbon solvent, and includes all dihydrocarbylmagnesium compounds and complexes of this compound with other metal compounds. is there. The relational expression nα + 2β = a + b + c of the symbols α, β, a, b, and c indicates the stoichiometry of the valence of the metal atom and the substituent.

In the above (formula 1), ^{the hydrocarbon group represented by R 2} and R ³ having 2 or more and 20 or less carbon atoms is not particularly limited, and is, for example, an alkyl group, a cycloalkyl group or an aryl group, and specifically. Examples include ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, cyclohexyl, phenyl group and the like. Among these, an alkyl group is preferable. When α> 0, as the metal atom M ¹ , a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table can be used, and examples thereof include zinc, boron and aluminum. Among these, aluminum and zinc are preferable.

The ratio of magnesium to the metal atom M ¹ : β / α is not particularly limited, but is preferably 0.1 or more and 30 or less, and more preferably 0.5 or more and 10 or less. Further, when a predetermined organic magnesium compound having α = 0 is used, for example, when R ² is 1-methylpropyl or the like, it is soluble in an inert hydrocarbon solvent, and such a compound is also used in the present embodiment. Gives favorable results. In the above (Equation 1), R ² and R ³ when α = 0 satisfy any one of the following three groups (1), (2), and (3). preferable.

Group (1): At ^{least one of R 2} and R ³ is a secondary or tertiary alkyl group having 4 or more and 6 or less carbon atoms, preferably ^{both R 2} and R ³ have 4 or more carbon atoms and 6 carbon atoms. The following alkyl groups, at least one of which is a secondary or tertiary alkyl group.
Group (2): R ² and R ³ are alkyl groups having different carbon atoms, preferably R ² is an alkyl group having 2 or 3 carbon atoms, and R ³ is 4 or more carbon atoms. Being an alkyl group of.
Group (3): At ^{least one of R 2} and R ³ is a hydrocarbon group having 6 or more carbon atoms, preferably an alkyl group having 12 or more when the number of carbon atoms contained in ^{R 2} and R ^{3 is added.} There is.

These groups will be specifically shown below.
Examples of the secondary or tertiary alkyl group having 4 or more and 6 or less carbon atoms in the group (1) include 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl and 2-. Examples thereof include ethylpropyl, 2,2-dimethylpropyl, 2-methylpentyl, 2-ethylbutyl, 2,2-dimethylbutyl, 2-methyl-2-ethylpropyl group and the like. In particular, a 1-methylpropyl group is preferable.

Further, examples of the alkyl group having 2 or 3 carbon atoms in the group (2) include ethyl, 1-methylethyl, propyl group and the like. In particular, an ethyl group is preferable. The alkyl group having 4 or more carbon atoms is not particularly limited, and examples thereof include butyl, pentyl, hexyl, heptyl, and octyl groups. In particular, butyl and hexyl groups are preferable.

Further, the hydrocarbon group having 6 or more carbon atoms in the group (3) is not particularly limited, and examples thereof include hexyl, heptyl, octyl, nonyl, decyl, phenyl, and 2-naphthyl group. Among the hydrocarbon groups, an alkyl group is preferable, and among the alkyl groups, a hexyl group and an octyl group are particularly preferable.

In general, as the number of carbon atoms contained in an alkyl group increases, it tends to be more soluble in an inert hydrocarbon solvent, and the viscosity of the solution tends to increase. Therefore, it is preferable in terms of handling to use an appropriately long-chain alkyl group. The organic magnesium compound can be diluted with an inert hydrocarbon solvent before use, but even if the solution contains or remains a trace amount of Lewis basic compounds such as ether, ester, and amine. It can be used without any problem.

Next, Y ¹ will be described. In the above (formula 1), Y ¹ is alkoxy, siloxy, allyloxy, amino, amide, -N = C-R ⁴ , R ⁵ , -SR ⁶ (where R ⁴ , R ⁵ and R ⁶ are independent of each other. It represents a hydrocarbon group having 2 or more and 20 or less carbon atoms) or a β-keto acid residue.

In the above (formula 1), ^{as the hydrocarbon group represented by R 4} , R ⁵ and R ⁶ , an alkyl group or an aryl group having 1 or more and 12 or less carbon atoms is preferable, and an alkyl group or an aryl group having 3 or more and 10 or less is preferable. Groups are more preferred. The hydrocarbon group is not limited to, for example, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 1,1-dimethylethyl, pentyl, hexyl, 2-methylpentyl, 2 Examples thereof include -ethylbutyl, 2-ethylpentyl, 2-ethylhexyl, 2-ethyl-4-methylpentyl, 2-propylheptyl, 2-ethyl-5-methyloctyl, octyl, nonyl, decyl, phenyl and naphthyl groups. In particular, butyl, 1-methylpropyl, 2-methylpentyl and 2-ethylhexyl groups are preferred.

Further, in the above (formula 1), Y ¹ is preferably an alkoxy group or a siloxy group. Alkoxy groups include, but are not limited to, methoxy, ethoxy, propoxy, 1-methylethoxy, butoxy, 1-methylpropoxy, 1,1-dimethylethoxy, pentoxy, hexoxy, 2-methylpentoxy, 2-. Examples thereof include ethyl butoxy, 2-ethylpentoxy, 2-ethylhexoxy, 2-ethyl-4-methylpentoxy, 2-propylheptoxy, 2-ethyl-5-methyloctoxy, octoxy, phenoxy and naphthoxy groups. In particular, butoxy, 1-methylpropoxy, 2-methylpentoxy and 2-ethylhexoxy groups are preferred.
Examples of the syroxy group include, but are not limited to, hydrodimethylsiloxy, ethylhydromethylsiloxy, diethylhydrosiloxy, trimethylsiloxy, ethyldimethylsiloxy, diethylmethylsiloxy, triethylsiloxy group and the like. In particular, hydrodimethylsiloxy, ethylhydromethylsiloxy, diethylhydrosiloxy, and trimethylsiloxy groups are preferable.

The method for synthesizing the organic magnesium compound (A-1) is not particularly limited, but for example, the formula R ² MgX ¹ and the formula R ² Mg (R ² has the above-mentioned meaning, and X ¹ is halogen. The organic magnesium compounds belonging to the group consisting of) and the formulas M ¹ R ³ _n and M ¹ R ³ _(n-1) H (M ¹ and R ³ have the above-mentioned meanings, and n is an atom ^{of M 1.} Organic metal compounds belonging to the group consisting of (representing valence) are reacted in an inert hydrocarbon solvent at 25 ° C. or higher and 150 ° C. or lower, and if necessary, subsequently in the formula Y ¹ −H (Y ¹ is described above). It can be synthesized by a method of reacting a compound represented by (), or a method of reacting an organic magnesium compound having a functional group represented by ^{Y 1 and / or an organic aluminum compound.} Among these, is reacted with a compound represented by soluble organomagnesium compound of the formula Y ¹ -H in an inert hydrocarbon solvent is not particularly limited as to the order of the reaction, for example, the formula in an organic magnesium compound how will the addition of a compound represented by Y ¹ -H, using any of the methods of the formula Y ¹ way going adding an organic magnesium compound into a compound represented by -H, or a method of gradually adding simultaneously both be able to.

^{In the present embodiment, the molar composition ratio c / (α + β) of Y 1 to} all metal atoms in the organic magnesium compound (A-1) is 0 ≦ c / (α + β) ≦ 2, and 0 ≦ c / (α + β). <1 is preferable. ^{When the molar composition ratio of Y 1 to} all metal atoms is 2 or less, the reactivity of the organic magnesium compound (A-1) with respect to the titanium compound (A-2) tends to be improved.

Next, the titanium compound (A-2) will be described. (A-2) is a titanium compound represented by the following (formula 2).
(A-2): Ti (OR ⁷ ) _d X ¹ _(4-d) ... (Equation 2)
(In Equation 2, d is a real number of 0 or more and 4 or less, R ⁷ is a hydrocarbon group having 1 or more carbon atoms and 20 or less, and X ¹ is a halogen atom.)

In the above (formula 2), d is preferably 0 or more and 1 or less, and more preferably 0. ^{The hydrocarbon group represented by R 7} in the above (formula 2) is not limited to the following, but for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, 2-ethylhexyl, heptyl, octyl, decyl, and the like. Examples thereof include aliphatic hydrocarbon groups such as allyl groups; alicyclic hydrocarbon groups such as cyclohexyl, 2-methylcyclohexyl and cyclopentyl groups; aromatic hydrocarbon groups such as phenyl and naphthyl groups. In particular, an aliphatic hydrocarbon group is preferable. Examples of the halogen represented by X ¹ include chlorine, bromine, and iodine. Chlorine is particularly preferable. In the present embodiment, the titanium compound (A-2) is particularly preferably titanium tetrachloride. In this embodiment, two or more compounds selected from the above can be mixed and used.

Next, the reaction between the organic magnesium compound (A-1) and the titanium compound (A-2) will be described.
The reaction is preferably carried out in an inert hydrocarbon solvent, more preferably in an aliphatic hydrocarbon solvent such as hexane or heptane. The molar ratio of the organic magnesium compound (A-1) to the titanium compound (A-2) in the reaction is not particularly limited, but Ti contained in (A-2) with respect to the Mg atom contained in (A-1). The molar ratio of atoms (Ti / Mg) is preferably 0.1 or more and 10 or less, and more preferably 0.3 or more and 3 or less. The reaction temperature is not particularly limited, but is preferably carried out in the range of -80 ° C or higher and 150 ° C or lower, and more preferably in the range of −40 ° C. or higher and 100 ° C. or lower.
The order of addition of the organic magnesium compound (A-1) and the titanium compound (A-2) is not particularly limited, and (A-1) is followed by (A-2), followed by (A-2). Either method of adding (A-1) or adding (A-1) and (A-2) at the same time is possible, but (A-1) and (A-2) are added at the same time. The method of doing is preferable. In the present embodiment, the solid catalyst component [A] obtained by the above reaction is used as a slurry solution using an inert hydrocarbon solvent.

As another example of the Cheegler-Natta catalyst component used in the present embodiment, it is composed of a solid catalyst component [C] and an organic metal compound component [B], and the solid catalyst component [C] is represented by the following (formula 3). A carrier (C-) prepared by reacting an organic magnesium compound (C-1) soluble in the represented inert hydrocarbon solvent with a chlorinating agent (C-2) represented by the following (formula 4). The organic magnesium compound (C-4) soluble in the activated carbon solvent represented by the following (formula 5) and the titanium compound (C-5) represented by the following (formula 6) are supported on 3). A catalyst for olefin polymerization produced by the above is preferable.

(C-1): (M ² ) γ (Mg) δ (R ⁸ ) _e (R ⁹ ) _f (OR ¹⁰ ) _g ... (Equation 3)
(In Equation 3, M ² is a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table, and R ⁸ , R ⁹ and R ¹⁰ are carbonized carbon atoms having 2 or more and 20 or less carbon atoms, respectively. It is a hydrogen group, and γ, δ, e, f and g are real numbers satisfying the following relationship. 0 ≦ γ, 0 <δ, 0 ≦ e, 0 ≦ f, 0 ≦ g, 0 <e + f, 0 ≦ g / (γ + δ) ≦ 2, kγ + 2δ = e + f + g (where k represents the valence of ^{M 2))}

(C-2): H _h SiCl _i R ¹¹ _{(4- (h + i))} ... (Equation 4)
(In Equation 4, R ¹¹ is a hydrocarbon group having 1 to 12 carbon atoms, and h and i are real numbers satisfying the following relationship. 0 <h, 0 <i, 0 <h + i ≦ 4)

(C-4): (M ¹ ) α (Mg) β (R ² ) _a (R ³ ) _b Y ¹ _c ... (Equation 5)
(In Equation 5, M ¹ is a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table, and R ² and R ³ are hydrocarbon groups having 2 to 20 carbon atoms. , Y ¹ is alkoxy, siloxy, allyloxy, amino, amide, -N = C-R ⁴ , R ⁵ , -SR ⁶ (where R ⁴ , R ⁵ and R ⁶ are hydrocarbons with 1 or more and 20 or less carbon atoms. Represents a group. When c is 2, Y ¹ may be different), β-ketoic acid residue, and α, β, a, b and c have the following relationship. It is a real number to be satisfied. 0 ≦ α, 0 <β, 0 ≦ a, 0 ≦ b, 0 ≦ c, 0 <a + b, 0 ≦ c / (α + β) ≦ 2, nα + 2β = a + b + c (where n is M ¹ Represents the valence of.)))

(C-5): Ti (OR ⁷ ) _d X ¹ _(4-d) ... (Equation 6)
(In Formula 6, d is a real number of 0 or more and 4 or less, R ⁷ is a hydrocarbon group having 1 or more carbon atoms and 20 or less, and X ¹ is a halogen atom.)

First, the organic magnesium compound (C-1) will be described. (C-1) is shown as a complex compound of organic magnesium soluble in an inert hydrocarbon solvent, but includes all of the dihydrocarbylmagnesium compounds and complexes of this compound with other metal compounds. It is a thing. The relational expression kγ + 2δ = e + f + g of the symbols γ, δ, e, f and g in (Equation 3) indicates the stoichiometry between the valence of the metal atom and the substituent.

In the above (Formula 3), the ^{hydrocarbon group represented by R 8} to R ⁹ is not particularly limited, but is, for example, an alkyl group, a cycloalkyl group, or an aryl group, respectively, and specifically, methyl and ethyl. , Propyl, butyl, pentyl, hexyl, octyl, decyl, cyclohexyl, phenyl group and the like. Particularly preferably, R ⁸ and R ⁹ are alkyl groups, respectively. When α> 0, as the metal atom M ² , a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table can be used, and examples thereof include zinc, boron and aluminum. In particular, aluminum and zinc are preferable.

The ratio δ / γ of magnesium to the metal atom M ² is not particularly limited, but is preferably 0.1 or more and 30 or less, and more preferably 0.5 or more and 10 or less. Further, when a predetermined organic magnesium compound having γ = 0 is used, for example, when R ⁸ is 1-methylpropyl or the like, it is soluble in an inert hydrocarbon solvent, and such a compound is also used in the present embodiment. Gives favorable results. In the above formula (Equation 3), R ⁸ and R ⁹ when γ = 0 is preferably any one of the following three groups (1), (2), and (3).

Group (1): At ^{least one of R 8} and R ⁹ is a secondary or tertiary alkyl group ^{having 4 or more and 6 or less carbon atoms, preferably both R 8} and R ⁹ have 4 or more and 6 or less carbon atoms. Yes, at least one is a secondary or tertiary alkyl group.
Group (2): R ⁸ and R ⁹ are alkyl groups having different carbon atoms, preferably R ⁸ is an alkyl group having 2 or 3 carbon atoms, and R ⁹ is an alkyl group having 4 or more carbon atoms. To be.
Group (3): At ^{least one of R 8} and R ⁹ is a hydrocarbon group having 6 or more carbon atoms, preferably an alkyl group having a sum of carbon atoms contained in ^{R 8} and R ^{9 of 12 or more.} ..

Hereinafter, these groups will be specifically shown. Examples of the secondary or tertiary alkyl group having 4 or more and 6 or less carbon atoms in the group (1) include 1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, 2-methylbutyl and 2-ethyl. Examples thereof include propyl, 2,2-dimethylpropyl, 2-methylpentyl, 2-ethylbutyl, 2,2-dimethylbutyl, 2-methyl-2-ethylpropyl group and the like. In particular, a 1-methylpropyl group is preferable.

In addition, examples of the alkyl group having 2 or 3 carbon atoms in the group (2) include ethyl, 1-methylethyl, and a propyl group. In particular, an ethyl group is preferable. The alkyl group having 4 or more carbon atoms is not particularly limited, and examples thereof include butyl, pentyl, hexyl, heptyl, and octyl groups. In particular, butyl and hexyl groups are preferable.

Further, the hydrocarbon group having 6 or more carbon atoms in the group (3) is not particularly limited, and examples thereof include hexyl, heptyl, octyl, nonyl, decyl, phenyl, and 2-naphthyl group. Among the hydrocarbon groups, an alkyl group is preferable, and among the alkyl groups, a hexyl group and an octyl group are more preferable.

In general, as the number of carbon atoms contained in an alkyl group increases, it tends to be more soluble in an inert hydrocarbon solvent, and the viscosity of the solution tends to increase. Therefore, it is preferable in terms of handling to use an appropriately long-chain alkyl group. Although the organic magnesium compound is used as an inert hydrocarbon solution, it does not matter if the solution contains or remains a trace amount of Lewis basic compounds such as ether, ester, and amine.

Next, the alkoxy group (OR ¹⁰ ) will be described.
As the ^{hydrocarbon group represented by R 10} , an alkyl group or an aryl group having 1 or more and 12 or less carbon atoms is preferable, and an alkyl group or an aryl group having 3 or more and 10 or less is more preferable. The R ¹⁰ is not particularly limited, but for example, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 1,1-dimethylethyl, pentyl, hexyl, 2-methylpentyl, 2-ethylbutyl, Examples thereof include 2-ethylpentyl, 2-ethylhexyl, 2-ethyl-4-methylpentyl, 2-propylheptyl, 2-ethyl-5-methyloctyl, octyl, nonyl, decyl, phenyl and naphthyl groups. In particular, butyl, 1-methylpropyl, 2-methylpentyl and 2-ethylhexyl groups are preferred.

The method for synthesizing the organic magnesium compound (C-1) is not particularly limited, but is composed of the formula: R ⁸ MgX ¹ and the formula: R ⁸ Mg (R ⁸ has the above-mentioned meaning, and X ¹ is a halogen atom). Organic magnesium compounds belonging to the group and organic metal compounds belonging to the group consisting of ^{the formula: M 2} R ⁹ _k and the formula: M ² R ⁹ _(k-1) H (M ² , R ^{9 and k have the above-mentioned meanings).} Is reacted in an inert hydrocarbon solvent at a temperature of 25 ° C. or higher and 150 ° C. or lower, and if necessary, an alcohol having a hydrocarbon group represented by ^{R 9} (R ^{9 has the above-mentioned meaning).} Alternatively, a method of reacting with an alkoxymagnesium compound having a hydrocarbon group represented by ^{R 9} and / or an alkoxyaluminum compound which is soluble in an inert hydrocarbon solvent is preferable.

Of these, when the organic magnesium compound soluble in the inert hydrocarbon solvent is reacted with the alcohol, the order of the reactions is not particularly limited, and the method of adding the alcohol to the organic magnesium compound and the organic magnesium in the alcohol Either a method of adding the compound or a method of adding both at the same time can be used. The reaction ratio of the organic magnesium compound soluble in the inert hydrocarbon solvent to the alcohol is not particularly limited, but the molar composition ratio of the alkoxy group to all metal atoms in the alkoxy group-containing organic magnesium compound obtained as a result of the reaction is g. / (Γ + δ) is preferably 0 ≦ g / (γ + δ) ≦ 2, and more preferably 0 ≦ g / (γ + δ) <1.

Next, the chlorinating agent (C-2) will be described. The chlorinating agent (C-2) is represented by the following (formula 4), and at least one is a silicon chloride compound having a Si—H bond.

(C-2): H _h SiCl _i R ¹¹ _{(4- (h + i))} ... (Equation 4)
(In Equation 4, R ¹¹ is a hydrocarbon group having 1 to 12 carbon atoms, and h and i are real numbers satisfying the following relationship. 0 <h, 0 <i, 0 <h + i ≦ 4)

^{The hydrocarbon group represented by R 11} in the above (formula 4) is not particularly limited, and examples thereof include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group, and specific examples thereof include an aromatic hydrocarbon group. , Methyl, ethyl, propyl, 1-methylethyl, butyl, pentyl, hexyl, octyl, decyl, cyclohexyl, phenyl group and the like. In particular, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 3 carbon atoms such as methyl, ethyl, propyl, and 1-methylethyl groups is more preferable. Further, h and i are numbers larger than 0 that satisfy the relationship of h + i ≦ 4, and i is preferably 2 or more and 3 or less.

The compound of these (C-2) is not particularly limited, but for example, HSiCl ₃ , HSiCl ₂ CH ₃ , HSiCl ₂ C ₂ H ₅ , HSiCl ₂ (C ₃ H ₇ ), HSiCl ₂ (2-C _3). H ₇ ), HSiCl ₂ (C ₄ H ₉ ), HSiCl ₂ (C ₆ H ₅ ), HSiCl ₂ (4-Cl-C ₆ H ₄ ), HSiCl ₂ (CH = CH ₂ ), HSiCl ₂ (CH ₂ C) ₆ H ₅ ), HSiCl ₂ (1-C ₁₀ H ₇ ), HSiCl ₂ (CH ₂ CH = CH ₂ ), H ₂ SiCl (CH ₃ ), H ₂ SiCl (C ₂ H ₅ ), HSiCl (CH ₃ ) ₂ , HSiCl (C ₂ H ₅ ) ₂ , HSiCl (CH ₃ ) (2-C ₃ H ₇ ), HSiCl (CH ₃ ) (C ₆ H ₅ ), HSiCl (C ₆ H ₅ ) _{2, and the} like. A silicon chloride compound consisting of these compounds or a mixture of two or more selected from these compounds is used as (C-2). In particular, HSiCl ₃ , HSiCl ₂ CH ₃ , HSiCl (CH ₃ ) ₂ , and HSiCl ₂ (C ₃ H ₇ ) are preferable, and HSiCl ₃ and HSiCl ₂ CH ₃ are more preferable.

Next, the reaction between the organic magnesium compound (C-1) and the chlorinating agent (C-2) will be described. In the reaction, (C-2) is previously subjected to an inert hydrocarbon solvent, chlorinated hydrocarbons such as 1,2-dichloroethane, o-dichlorobenzene and dichloromethane; ether-based media such as diethyl ether and tetrahydrofuran; or these. It is preferable to use it after diluting it with a mixed medium. Of these, an inert hydrocarbon solvent is more preferable in terms of catalyst performance.
The reaction ratio between (C-1) and (C-2) is not particularly limited, but the silicon atom contained in (C-2) is 0.01 mol or more and 100 mol with respect to 1 mol of magnesium atom contained in (C-1). It is preferably 0.1 mol or more and 10 mol or less.

The reaction method between the organic magnesium compound (C-1) and the chlorinating agent (C-2) is not particularly limited, and (C-1) and (C-2) are simultaneously introduced into the reactor and reacted. The method of simultaneous addition, the method of charging (C-2) into the reactor in advance and then introducing (C-1) into the reactor, or the method of charging (C-1) into the reactor in advance and then (C-). Any method of introducing 2) into the reactor can be used. Among these, a method in which (C-2) is charged into the reactor in advance and then (C-1) is introduced into the reactor is preferable. The carrier (C-3) obtained by the above reaction is preferably separated by a filtration or decantation method and then thoroughly washed with an inert hydrocarbon solvent to remove unreacted substances or by-products. ..

The reaction temperature between the organic magnesium compound (C-1) and the chlorinating agent (C-2) is not particularly limited, but is preferably 25 ° C. or higher and 150 ° C. or lower, and 30 ° C. or higher and 120 ° C. or lower. More preferably, it is 40 ° C. or higher and 100 ° C. or lower.
In the method of simultaneous addition in which (C-1) and (C-2) are simultaneously introduced into the reactor and reacted, the temperature of the reactor is adjusted to a predetermined temperature in advance, and the simultaneous addition is performed in the reactor. It is preferable to adjust the reaction temperature to a predetermined temperature by adjusting the temperature to a predetermined temperature.
In the method of introducing (C-1) into the reactor after charging (C-2) into the reactor in advance, the temperature of the reactor charged with the silicon chloride compound is adjusted to a predetermined temperature, and the organic magnesium is prepared. It is preferable to adjust the reaction temperature to a predetermined temperature by adjusting the temperature inside the reactor to a predetermined temperature while introducing the compound into the reactor.
In the method in which (C-1) is charged into the reactor in advance and then (C-2) is introduced into the reactor, the temperature of the reactor charged with (C-1) is adjusted to a predetermined temperature, and (C) is charged. It is preferable to adjust the reaction temperature to a predetermined temperature by adjusting the temperature inside the reactor to a predetermined temperature while introducing -2) into the reactor.

Next, the organic magnesium compound (C-4) will be described. As (C-4), the one represented by the following (Equation 5): (C-4) is preferable.

(C-4): (M ¹ ) α (Mg) β (R ² ) _a (R ³ ) _b Y ¹ _c ... (Equation 5)
(In Equation 5, M ¹ is a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table, and R ² and R ³ are hydrocarbon groups having 2 or more and 20 or less carbon atoms. , Y ¹ is alkoxy, siloxy, allyloxy, amino, amide, -N = C-R ⁴ , R ⁵ , -SR ⁶ (where R ⁴ , R ⁵ and R ⁶ are hydrocarbons with 1 or more and 20 or less carbon atoms. Represents a group. When c is 2, Y ¹ may be different), β-ketoic acid residue, and α, β, a, b and c have the following relationship. It is a real number to be satisfied. 0 ≦ α, 0 <β, 0 ≦ a, 0 ≦ b, 0 <a + b, 0 ≦ c / (α + β) ≦ 2, nα + 2β = a + b + c (where n is the atomic value of ^{M 1} Represents.)))

The amount of the organic magnesium compound (C-4) used may be 0.1 or more and 10 or less in terms of the molar ratio of the magnesium atom contained in (C-4) to the titanium atom contained in the titanium compound (C-5). It is preferably 0.5 or more and 5 or less, more preferably.

The temperature of the reaction between the organic magnesium compound (C-4) and the titanium compound (C-5) is not particularly limited, but is preferably -80 ° C or higher and 150 ° C or lower, and is in the range of -40 ° C or higher and 100 ° C or lower. Is more preferable.

The concentration of the organic magnesium compound (C-4) at the time of use is not particularly limited, but is preferably 0.1 mol / L or more and 2 mol / L or less based on the titanium atom contained in (C-4). More preferably, it is 5 mol / L or more and 1.5 mol / L or less. It is preferable to use an inert hydrocarbon solvent for diluting (C-4).

The order of addition of the organic magnesium compound (C-4) and the titanium compound (C-5) to the carrier (C-3) is not particularly limited, and (C-4) is followed by (C-5). Either method of adding (C-4) after C-5) or adding (C-4) and (C-5) at the same time is possible. Among these, a method of adding (C-4) and (C-5) at the same time is preferable. The reaction between (C-4) and (C-5) is carried out in an inert hydrocarbon solvent, and it is preferable to use an aliphatic hydrocarbon solvent such as hexane or heptane. The catalyst thus obtained is used as a slurry solution using an inert hydrocarbon solvent.

Next, the titanium compound (C-5) will be described. In the present embodiment, (C-5) is a titanium compound represented by the following (formula 6).

(C-5): Ti (OR ⁷ ) _d X ¹ _(4-d) ... (Equation 6)
(In Formula 6, d is a real number of 0 or more and 4 or less, R ⁷ is a hydrocarbon group having 1 or more carbon atoms and 20 or less, and X ¹ is a halogen atom.)

^{The hydrocarbon group represented by R 7} in (Formula 6) is not particularly limited, and for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, 2-ethylhexyl, heptyl, octyl, decyl, allyl group and the like. An aliphatic hydrocarbon group; an alicyclic hydrocarbon group such as cyclohexyl, 2-methylcyclohexyl, or cyclopentyl group; an aromatic hydrocarbon group such as phenyl or naphthyl group may be mentioned. Of these, an aliphatic hydrocarbon group is preferable. The ^{halogen represented by X 1} is not particularly limited, and examples thereof include chlorine, bromine, and iodine. Of these, chlorine is preferable. The titanium compound (C-5) selected from the above may be used alone or in combination of two or more.

The amount of the titanium compound (C-5) used is not particularly limited, but the molar ratio to the magnesium atom contained in the carrier (C-3) is preferably 0.01 or more and 20 or less, and particularly preferably 0.05 or more and 10 or less. ..

The reaction temperature of the titanium compound (C-5) is not particularly limited, but is preferably −80 ° C. or higher and 150 ° C. or lower, and more preferably −40 ° C. or higher and 100 ° C. or lower.
The method for supporting the titanium compound (C-5) on the carrier (C-3) described above is not particularly limited, and a method for reacting an excess (C-5) with (C-3) or a third component Although a method of efficiently supporting (C-5) may be used by using the above, a method of supporting (C-5) by the reaction of the organic magnesium compound (C-4) is preferable.

Next, the organometallic compound component [B] constituting the Ziegler-Natta catalyst used for producing the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment will be described.
The solid catalyst component [C] becomes a highly active polymerization catalyst when combined with the organometallic compound component [B].
The organometallic compound component [B] is sometimes called a "cocatalyst". The organometallic compound component [B] is preferably a compound containing a metal belonging to the group consisting of Group 1, Group 2, Group 12, and Group 13 of the Periodic Table, and is particularly preferably an organoaluminum compound and /. Alternatively, an organic magnesium compound is preferable.

As the organoaluminum compound as the organometallic compound component [B], it is preferable to use the compound represented by the following (formula 7) alone or in combination.

AlR ¹² _j Z ¹ _(3-j)・ ・ ・ (Equation 7)
(In Formula 7, R ¹² is a hydrocarbon group having 1 or more and 20 or less carbon atoms, Z ¹ is a group belonging to the group consisting of hydrogen, halogen, alkoxy, allyloxy, and siloxy groups, and j is a number of 2 or more and 3 or less. is there.)

In the above (formula 7), ^{the hydrocarbon group represented by R 12} having 1 or more and 20 or less carbon atoms is not particularly limited, and includes, for example, an aliphatic hydrocarbon, an aromatic hydrocarbon, and an alicyclic hydrocarbon. For example, trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, tri (2-methylpropyl) aluminum (or triisobutylaluminum), tripentylaluminum, tri (3-methylbutyl) aluminum, trihexylaluminum. , Trialkylaluminum such as trioctylaluminum and tridecylaluminum, diethylaluminum chloride, ethylaluminum dichloride, bis (2-methylpropyl) aluminum chloride, ethylaluminum sesquichloride, diethylaluminum bromide and other halogenated aluminum compounds, diethylaluminum ethoxy Alkoxyaluminum compounds such as do, bis (2-methylpropyl) aluminum butoxide, syroxyaluminum compounds such as dimethylhydrosiloxyaluminum dimethyl, ethylmethylhydrosiloxyaluminum diethyl and ethyldimethylsiloxyaluminum diethyl, and mixtures thereof are preferred. In particular, trialkylaluminum compounds are more preferred.

As the organomagnesium compound as the organometallic compound component [B], an organomagnesium compound soluble in the above-mentioned and the inert hydrocarbon solvent represented by the following (formula 3) is preferable.

(M ² ) γ (Mg) δ (R ⁸ ) _e (R ⁹ ) _f (OR ¹⁰ ) _g ... (Equation 3)
(In Equation 3, M ² is a metal atom belonging to the group consisting of groups 12, 13 and 14 of the periodic table, and R ⁸ , R ⁹ and R ¹⁰ are carbonized carbon atoms having 2 or more and 20 or less carbon atoms, respectively. It is a hydrogen group, and γ, δ, e, f and g are real numbers satisfying the following relationship. 0 ≦ γ, 0 <δ, 0 ≦ e, 0 ≦ f, 0 ≦ g, 0 <e + f, 0 ≦ g / (γ + δ) ≦ 2, kγ + 2δ = e + f + g (where k represents the valence of ^{M 2))}

This organic magnesium compound is shown in the form of a complex of organic magnesium soluble in an inert hydrocarbon solvent, but includes all of the dialkylmagnesium compounds and complexes of this compound with other metal compounds. is there. γ, δ, e, f, g, M ² , R ⁸ , R ⁹ , and OR ¹⁰ have already been described, but since this organic magnesium compound preferably has high solubility in an inert hydrocarbon solvent, it is preferable. δ / γ is preferably in the range of 0.5 or more and 10 or less, ^{and a compound in which M 2} is aluminum is more preferable.
The combination ratio of the solid catalyst component and the organometallic compound component [B] is not particularly limited, but the amount of the organometallic compound component [B] is preferably 1 mmol or more and 3,000 mmol or less with respect to 1 g of the solid catalyst component.

<Metallocene catalyst>
As the metallocene catalyst, a general transition metal compound is used.
The method for producing the metallocene catalyst is not particularly limited, and examples thereof include the production method described in Japanese Patent No. 4868853. Such metallocene catalysts include (a) a transition metal compound having a cyclic η-binding anion ligand, and (b) an activator capable of forming a complex that reacts with the transition metal compound to exhibit catalytic activity. It is composed of two catalyst components.

The transition metal compound having the cyclic η-bonding anion ligand (a) can be represented by, for example, the following (Equation 8).
L ¹ _j W _k M ³ X ² _p X ³ _q・ ・ ・ (Equation 8)

In the above (formula 8), L ¹ is independently composed of a group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents the η-binding cyclic anion ligand of choice, which in some cases has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms. , Halogen atom, halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, aminohydrocarbyl group having 1 to 12 carbon atoms, hydrocarbyloxy group having 1 to 12 carbon atoms, dihydrocarbylamino group having 1 to 12 carbon atoms, 1 carbon group. It is a substituent having up to 20 non-hydrogen atoms selected from the group consisting of ~ 12 hydrocarbylphosphino groups, silyl groups, aminosilyl groups, hydrocarbyloxysilyl groups having 1 to 12 carbon atoms, and halosilyl groups.

In the (Formula 8), M ³ may take the form oxidation number + 2, a transition metal selected from transition metals belonging to Group 4 of the periodic table of the + 3 or +4, at least one ligand L ¹ eta ⁵ Represents a bonded transition metal.

In the above formula (Equation 8), W is a divalent substituent having up to 50 non-hydrogen atoms, and is bonded to L ¹ and M ³ with a valence of 1 valence each, whereby L ^{1 is formed.} Represents a divalent substituent that cooperates with M ^{3 to form a metallocycle, and X 2} independently binds to the monovalent anionic σ-bonded ligand, M ³ and divalent. 60 selected from the group consisting of a divalent anionic σ-bonded ligand and a divalent anionic σ-bonded ligand that binds to L ¹ and M ^{3 with a valence of 1 valence each.} Represents an anionic sigma-bonded ligand having up to non-hydrogen atoms.

In the above (formula 8), X ² independently represents a neutral Lewis base-coordinating compound having up to 40 non-hydrogen atoms, and X ³ represents a neutral Lewis base-coordinating compound. ..

j is 1 or 2, but when j is 2, the two ligands L ¹ may bond to each other via a divalent group having up to 20 non-hydrogen atoms. The divalent group is a hydrocarbaziyl group having 1 to 20 carbon atoms, a halohydrocarbaziyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, and a hydrocarbazole group having 1 to 12 carbon atoms. It is a group selected from the group consisting of an amino group, a silanediyl group, a halosilanediyl group, and a silyleneamino group.

k is 0 or 1, p is 0, 1 or 2, where X ² is a monovalent anionic sigma-bonded ligand, or a divalent combination of ^{L 1} and M ³ If an anionic σ-bound ligand, p is 1 or more integer smaller than form oxidation number of M ^3, also divalent anionic σ-bound coordination which X ² is bonded only to M ³ In the case of a child, p is ^{an integer smaller than the formal oxidation number of M 3} by (j + 1) or more, and q is 0, 1 or 2.

^{Examples of the ligand X 2} in the compound of the above formula (Equation 8) include halide, a hydrocarbon group having 1 to 60 carbon atoms, a hydrocarbyloxy group having 1 to 60 carbon atoms, and a hydrocarbylamide group having 1 to 60 carbon atoms. , Hydrocarbylphosphosfide group having 1 to 60 carbon atoms, hydrocarbylsulfide group having 1 to 60 carbon atoms, silyl group, complex group thereof and the like.

^{Examples of the neutral Lewis base-coordinating compound X 3} in the compound of the above formula (Equation 8) include phosphine, ether, amine, olefin having 2 to 40 carbon atoms, diene having 1 to 40 carbon atoms, and these compounds. Examples include the induced divalent group.

As the transition metal compound having the (a) cyclic η-binding anion ligand constituting the metallocene catalyst, the transition metal compound represented by the above (formula 8) (however, j = 1) is preferable. Preferred examples of the compound represented by the above formula (formula 8) (where j = 1) include the compound represented by the following formula (formula 9).

In the above (formula 9), M ⁴ is a transition metal selected from the group consisting of titanium, zirconium, nickel, and hafnium, and represents a transition metal having a formal oxidation number of +2, +3, or +4. Each of R ¹³ is independently selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 8 carbon atoms, a silyl group, a gelmil group, a cyano group, a halogen atom and a composite group thereof, and up to 20 non-groups. Represents a substituent having a hydrogen atom, except that when the substituent R ¹³ is a hydrocarbon group having 1 to 8 carbon atoms, a silyl group or a gelmil group, in some cases, two adjacent substituents R ¹³ are bonded to each other. to form a divalent group, thereby to form a ring bond and in cooperation with between two carbon atoms of the cyclopentadienyl ring bonded respectively to the substituent R ¹³ that are adjacent of the two it can.

In the above (formula 9) ^{, each of X 4} independently contains halide, a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbyloxy group having 1 to 18 carbon atoms, a hydrocarbylamino group having 1 to 18 carbon atoms, and a silyl group. , Up to 20 non-hydrogen atoms selected from the group consisting of a hydrocarbylamide group having 1 to 18 carbon atoms, a hydrocarbylphosfide group having 1 to 18 carbon atoms, a hydrocarbylsulfide group having 1 to 18 carbon atoms and a complex group thereof. It represents a substituent having, however, in some cases it is possible to form two substituents X ⁴ is cooperatively neutral conjugated dienes having 4 to 30 carbon atoms or a divalent group.

In the above (formula 9), Y ² represents −O−, −S−, −NR ^* − or −PR ^* −, where R ^* is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, and the like. It represents a hydrocarbyloxy group having 1 to 8 carbon atoms, a silyl group, an alkyl halide group having 1 to 8 carbon atoms, an aryl halide group having 6 to 20 carbon atoms, or a composite group thereof.

In the above (Equation 9), Z ² represents SiR ^* ₂ , CR ^* ₂ , SiR ^* ₂ SiR ^* ₂ , CR ^* ₂ CR ^{* 2} , CR ^* = CR ^* , CR ^* ₂ SiR ^* ₂ or GeR ^* ₂ . However, R ^* is as defined above, and n is 1, 2 or 3.

Examples of the transition metal compound having the (a) cyclic η-binding anion ligand constituting the metallocene catalyst used in the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment are as follows. Examples include the compounds shown.
The zirconium-based compound is not particularly limited, and is, for example, bis (methylcyclopentadienyl) zirconium dimethyl, bis (n-butylcyclopentadienyl) zirconium dimethyl, bis (indenyl) zirconium dimethyl, and bis (1,3-). Dimethylcyclopentadienyl) zirconium dimethyl, (pentamethylcyclopentadienyl) (cyclopentadienyl) zirconium dimethyl, bis (cyclopentadienyl) zirconium dimethyl, bis (pentamethylcyclopentadienyl) zirconium dimethyl, bis ( Fluolenyl) zirconium dimethyl, ethylenebis (indenyl) zirconium dimethyl, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dimethyl, ethylenebis (4-methyl-1-indenyl) zirconium dimethyl, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) 5-Methyl-1-indenyl) zirconium dimethyl, ethylenebis (6-methyl-1-indenyl) zirconium dimethyl, ethylenebis (7-methyl-1-indenyl) zirconium dimethyl, ethylenebis (5-methoxy-1-indenyl) Zirconium dimethyl, ethylene bis (2,3-dimethyl-1-indenyl) zirconium dimethyl, ethylene bis (4,7-dimethyl-1-indenyl) zirconium dimethyl, ethylene bis- (4,7-dimethoxy-1-indenyl) zirconium Dimethyl, methylenebis (cyclopentadienyl) zirconium dimethyl, isopropylidene (cyclopentadienyl) zirconium dimethyl, isopropylidene (cyclopentadienyl-fluorenyl) zirconium dimethyl, silylenebis (cyclopentadienyl) zirconium dimethyl, dimethylsilylene (cyclo) Pentazienyl) Zirconium dimethyl and the like can be mentioned.

The titanium compound is not particularly limited, for example, [(N-t-butylamido) (tetramethyl-eta ⁵ - cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl, [(N-t-butylamide ) (Tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] Titanium dimethyl, [(N-methylamide) (Tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] Titanium dimethyl, [(N-phenylamide) (Tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] Titanium dimethyl, [(N-benzylamide) (Tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] Titanium dimethyl, [(N-t-butyramide) ) (Η ⁵ -cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl, [(N-t-butyramide) (η ⁵ -cyclopentadienyl) dimethylsilane] titanium dimethyl, [(N-methylamide) ( η ⁵ -cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl, [(N-methylamide) (η ⁵ -cyclopentadienyl) dimethylsilane] titanium dimethyl, [(N-t-butyramide) (η ⁵⁾ - include indenyl) dimethylsilane] titanium dimethyl, etc. - indenyl) dimethylsilane] titanium dimethyl, [(N-benzylamide) (eta ^5.

The nickel-based compound is not particularly limited, and is, for example, dibromobistriphenylphosphine nickel, dichlorobistriphenylphosphine nickel, dibromodiacethan nickel, dibromodibenzonitrile nickel, dibromo (1,2-bisdiphenylphosphinoetan) nickel, and dibromo. (1,3-bisdiphenylphosphinopropane) nickel, dibromo (1,1'-diphenylbisphosphinoferosen) nickel, dimethylbisdiphenylphosphine nickel, dimethyl (1,2-bisdiphenylphosphinoetan) nickel, methyl (1,3-bisdiphenylphosphinoetan) 1,2-bisdiphenylphosphinoetan) nickel tetrafluoroborate, (2-diphenylphosphino-1-phenylethyleneoxy) phenylpyridine nickel, dichlorobistriphenylphosphine palladium, dichlorodibenzonitrile palladium, dichlorodiacetone palladium, dichloro ( 1,2-bisdiphenylphosphinoetan) palladium, bistriphenylphosphine palladium bistetrafluoroborate, bis (2,2'-bipyridine) methyl iron tetrafluoroborate etherate and the like can be mentioned.

The hafnium-based compound is not particularly limited, for example, [(N-t-butylamido) (tetramethyl-eta ⁵ - cyclopentadienyl) -1,2-ethanediyl] hafnium dimethyl, [(N-t-butylamide ) (tetramethyl-eta ⁵ - cyclopentadienyl) dimethyl silane] hafnium dimethyl, [(N-methylamide) (tetramethyl-eta ⁵ - cyclopentadienyl) dimethyl silane] hafnium dimethyl, [(N-phenyl amide) (Tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] hafnium dimethyl, [(N-benzylamide) (tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] hafnium dimethyl, [(N-t-butylamide) ) (Η ⁵ -cyclopentadienyl) -1,2-ethanediyl] hafnium dimethyl, [(N-t-butylamide) (η ⁵ -cyclopentadienyl) dimethylsilane] hafnium dimethyl, [(N-methylamide) ( η ⁵ -cyclopentadienyl) -1,2-ethanediyl] hafnium dimethyl, [(N-methylamide) (η ⁵ -cyclopentadienyl) dimethylsilane] hafnium dimethyl, [(N-t-butylamide) (η ⁵⁾ - include indenyl) dimethylsilane] hafnium dimethyl, etc. - indenyl) dimethylsilane] hafnium dimethyl, [(N-benzylamide) (eta ^5.

Further, the transition metal compound having the (a) cyclic η-binding anion ligand constituting the metallocene catalyst used in the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment is described above. The "dimethyl" part of the name of each zirconium-based compound and the titanium-based compound (this appears immediately after the part at the end of the name of each compound, that is, the part called "zylene" or "titanium", and the above formula which is the name corresponding to the portion of the X ⁴ in 2), for example, "dichloro", "dibromo", "diiodo", "diethyl", "dibutyl", "diphenyl", "dibenzyl,""2- ( N, N-dimethylamino) benzyl "," 2-butene-1,4-diyl "," s- trans -η4-1,4- diphenyl-1,3-butadiene, "" s- trans eta ⁴ - 3-methyl-1,3-pentadiene "," s- trans eta ^{4-1,4-dibenzyl-1,3-butadiene,} "" s- trans eta ^{4-2,4-hexadiene,} "" s- trans eta ⁴ -1,3-pentadiene "," s- trans eta ^{4-1,4-ditolyl-1,3-butadiene,} "" s- trans eta ^4-1,4-bis (trimethylsilyl) - 1,3-butadiene, "" s- cis eta ^{4-1,4-diphenyl-1,3-butadiene,} "" s- cis eta ^{4-3-methyl-1,3-pentadiene} "," s- cis eta ^{4-1,4-dibenzyl-1,3-butadiene,} "" s- cis eta ^{4-2,4-hexadiene,} "" s- cis eta ⁴ -1,3-pentadiene "," s - cis eta ^{4-1,4-ditolyl-1,3-butadiene} ", instead any of such" s- cis eta ^4-1,4-bis (trimethylsilyl) -1,3-butadiene " There are also compounds with names that can be used.

The transition metal compound having the (a) cyclic η-binding anion ligand constituting the metallocene catalyst, which is used in the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment, is generally known by a known method. Can be synthesized. In the present embodiment, these transition metal compounds may be used alone or in combination.

Next, an activator capable of forming a complex that reacts with (b) a transition metal compound and exhibits catalytic activity, which is used in the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment (hereinafter, , Simply referred to as "activator") ".
Examples of the activator include compounds defined by the following (formula 10).
[L ^2- H] ^{d +} [M ⁵ _m Q _p ] ^{d -...} (Equation 10)
(In Equation 10, [L ^2- H] ^{d +} represents the proton-donating Bronsted acid, where L ² represents the neutral Lewis base and d is an integer of 1-7; [M ⁵ _m. Q _p ] ^d- represents a compatible non-coordinating anion, where M ⁵ represents a metal or metalloid belonging to any of the 5th to 15th groups of the periodic table, and Q is independent of each other. Hydride, halide, dihydrocarbylamide groups with 2 to 20 carbon atoms, hydrocarbyloxy groups with 1 to 30 carbon atoms, hydrocarbon groups with 1 to 30 carbon atoms, and substituted hydrocarbon groups with 1 to 40 carbon atoms. Selected from the group consisting of, where the number of Qs that are halides is 1 or less, m is an integer of 1-7, p is an integer of 2-14, and d is as defined above. Yes, pm = d.)

The non-coordinating anion is not particularly limited, and is, for example, tetrakisphenyl borate, tri (p-tolyl) (phenyl) borate, tris (pentafluorophenyl) (phenyl) borate, tris (2,4-dimethylphenyl). (Hydphenyl) borate, tris (3,5-dimethylphenyl) (phenyl) borate, tris (3,5-di-trifluorimethylphenyl) (phenyl) borate, tris (pentafluorophenyl) (cyclohexyl) borate, tris ( Pentafluorophenyl) (naphthyl) borate, tetrakis (pentafluorophenyl) borate, triphenyl (hydroxyphenyl) borate, diphenyl-di (hydroxyphenyl) borate, triphenyl (2,4-dihydroxyphenyl) borate, tri (p-) Trill) (hydroxyphenyl) borate, tris (pentafluorophenyl) (hydroxyphenyl) borate, tris (2,4-dimethylphenyl) (hydroxyphenyl) borate, tris (3,5-dimethylphenyl) (hydroxyphenyl) borate, Tris (3,5-di-trifluorimethylphenyl) (hydroxyphenyl) borate, tris (pentafluorophenyl) (2-hydroxyethyl) borate, tris (pentafluorophenyl) (4-hydroxybutyl) borate, tris (penta) Fluorophenyl) (4-hydroxy-cyclohexyl) borate, tris (pentafluorophenyl) (4- (4'-hydroxyphenyl) phenyl) borate, tris (pentafluorophenyl) (6-hydroxy-2-naphthyl) borate, etc. Can be mentioned.

Other preferred non-coordinating anions include borate in which the hydroxy group of the above-exemplified borate is replaced with an NHR group. Here, R is preferably a methyl group, an ethyl group or a tert-butyl group.

The proton-imparting blended acid is not particularly limited, and is, for example, triethylammonium, tripropylammonium, tri (n-butyl) ammonium, trimethylammonium, tributylammonium, tri (n-octyl) ammonium and the like. Alkyl-substituted ammonium cations; N, such as N, N-dimethylanilinium, N, N-diethylanilinium, N, N-2,4,6-pentamethylanilinium, N, N-dimethylbenzylanilinium, etc. N-Dialkylanilinium cation; Dialkylammonium cation such as di- (i-propyl) ammonium, dicyclohexylammonium; Tria such as triphenylphosphonium, tri (methylphenyl) phosphonium, tri (dimethylphenyl) phosphonium Lylphosphonium cation; or dimethylsulfonium, diethylfluphonium, diphenylsulphonium and the like.

Further, as an activator used in the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment, an organometallic oxy compound having a unit represented by the following (Formula 11) can also be used.

(Here, M ⁶ is a metal or metalloid of groups 13 to 15 of the periodic table, R ¹⁴ is an independently hydrocarbon group or a substituted hydrocarbon group having 1 to 12 carbon atoms, and n is a metal. It is a valence of M ⁶ , and m is an integer of 2 or more.)

A preferable example of the activator used for producing the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment is, for example, an organoaluminum oxy compound containing a unit represented by the following (formula 12).

(Here, R ¹⁵ is an alkyl group having 1 to 8 carbon atoms, and m is an integer of 2 to 60.)

A more preferable example of the activator used for producing the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment is methylarmoxane containing a unit represented by the following (Formula 13).

(Here, m is an integer of 2 to 60.)

In the present embodiment, the activator component may be used alone or in combination of two or more.

In the production of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment, these catalyst components can be supported on a solid component and used as a supported catalyst. Such solid components are not particularly limited, but specifically, for example, a porous polymer material such as a copolymer of polyethylene, polypropylene or styrene divinylbenzene; silica, alumina, magnesia, magnesium chloride, zirconia, titania, etc. Inorganic solid materials of Group 2, 3, 4, 13 and 14 elements of the periodic table such as boron oxide, calcium oxide, zinc oxide, barium oxide, vanadium pentoxide, chromium oxide and thorium oxide; and mixtures thereof; Included are at least one inorganic solid material selected from the double oxides of.

The composite oxide of silica is not particularly limited, and examples thereof include a composite oxide of silica such as silica magnesia and silica alumina and a group 2 or 13 element of the periodic table. Further, in the present embodiment, in addition to the above two catalyst components, an organoaluminum compound can be used as a catalyst component, if necessary.
The organoaluminum compound that can be used in this embodiment is, for example, a compound represented by the following (formula 14).

(Here, R ¹⁶ is an alkyl group having 1 to 12 carbon atoms and an aryl group having 6 to 20 carbon atoms, X ⁵ is a halogen, hydrogen or alkoxyl group, and the alkyl group is linear, branched or branched. It is cyclic and n is an integer of 1-3.)

Here, the organoaluminum compound as a catalyst component may be a mixture of the compounds represented by the above (formula 14). As the organic aluminum compound, for example, in the above (formula 14), R ¹⁶ is a methyl group, an ethyl group, a butyl group, an isobutyl group, a hexyl group, an octyl group, a decyl group, a phenyl group, a tolyl group or the like. Examples thereof include those in which X ⁵ is a methoxy group, an ethoxy group, a butoxy group, a chloro and the like.

In the present embodiment, the organoaluminum compound that can be used as a catalyst component is not particularly limited, but for example, trimethylaluminum, triethylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum and the like. Or, reaction products of these organoaluminums with alcohols such as methyl alcohol, ethyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, octyl alcohol and decyl alcohol, such as dimethylmethoxyaluminum, diethylethoxyaluminum, dibutylbutoxyaluminum and the like. Can be mentioned.

Examples of the polymerization method of the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment include a method of (co) polymerizing ethylene or a monomer containing ethylene by a suspension polymerization method or a vapor phase polymerization method. Be done. Among these, a suspension polymerization method capable of efficiently removing heat of polymerization is preferable. In the suspension polymerization method, an inert hydrocarbon medium can be used as the medium, and the olefin itself can also be used as the solvent.

The inert hydrocarbon medium is not particularly limited, and is, for example, an aliphatic hydrocarbon such as propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, decane, dodecane, kerosene; cyclopentane, cyclohexane, methyl. Aliphatic hydrocarbons such as cyclopentane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethyl chloride, chlorobenzene and dichloromethane; or mixtures thereof.

(Polymerization conditions)
The polymerization temperature in the method for producing an ethylene polymer contained in the polyethylene resin composition of the present embodiment is usually 30 ° C. or higher and 100 ° C. or lower.
When the polymerization temperature is 30 ° C. or higher, industrially more efficient production tends to be possible. On the other hand, when the polymerization temperature is 100 ° C. or lower, continuous and more stable operation tends to be possible.

Further, the polymerization pressure in the method for producing a polyethylene polymer contained in the polyethylene resin composition of the present embodiment is usually normal pressure or more and 2 MPa or less. The polymerization pressure is preferably 0.1 MPa or more, more preferably 0.12 MPa or more, and more preferably 1.5 MPa or less, more preferably 1.0 MPa or less. When the polymerization pressure is equal to or higher than normal pressure, industrially more efficient production tends to be possible, and when the polymerization pressure is 2 MPa or less, partial heat generation due to the rapid polymerization reaction at the time of introducing the catalyst is suppressed. There is a tendency that polyethylene can be produced stably.

The polymerization reaction can be carried out by any of a batch method, a semi-continuous method and a continuous method, but it is preferable to carry out the polymerization by a continuous method. By continuously supplying ethylene gas, solvent, catalyst, etc. into the polymerization system and continuously discharging it together with the produced polyethylene, it is possible to suppress a partial high temperature state due to a rapid ethylene reaction, and polymerization is possible. The system becomes more stable. When ethylene reacts in a uniform state in the system, the formation of branches and double bonds in the polymer chain is suppressed, and the molecular weight of polyethylene is reduced and cross-linking is less likely to occur. Melting or the amount of unmelted material remaining at the time of melting is reduced, coloring is suppressed, and problems such as deterioration of mechanical properties are less likely to occur. Therefore, a continuous equation in which the inside of the polymerization system is more uniform is preferable.

It is also possible to carry out the polymerization in two or more stages having different reaction conditions. Further, for example, as described in Japanese Patent Application Publication No. 3127133, the ultimate viscosity of the obtained polyethylene is controlled by the presence of hydrogen in the polymerization system or by changing the polymerization temperature. May be good. Specifically, by adding hydrogen as a chain transfer agent into the polymerization system, it is possible to control the ultimate viscosity within an appropriate range. When hydrogen is added into the polymerization system, the molar fraction of hydrogen is preferably 0 mol% or more and 30 mol% or less, more preferably 0 mol% or more and 25 mol% or less, and 0 mol% or more and 20 mol% or less. Is even more preferable. In addition to the above-mentioned components, the present embodiment may contain other known components useful for producing polyethylene.

When polymerizing the ethylene-based polymer constituting the polyethylene resin composition of the present embodiment, in order to suppress the adhesion of the polymer to the polymerization reactor, Stadis 450 or the like manufactured by The Assisted Octel Company (distributor Maruwa Bussan), etc. It is preferable to use an antistatic agent. Stadis450 can be added to the polymerization reactor by diluting it with an inert hydrocarbon medium by a pump or the like. The amount added at this time is preferably in the range of 0.10 ppm or more and 20 ppm or less, and preferably in the range of 0.20 ppm or more and 10 ppm or less, based on the production amount of the ethylene polymer per unit time. More preferred.

In the method for producing an ethylene polymer contained in the polyethylene resin composition of the present embodiment, it is preferable to adjust the temperature of the catalyst charged into the reactor to less than 5 ° C. Further, it is preferable that hexane in which ethylene is dissolved is introduced into the reactor from the hexane feed port at a temperature lower than 5 ° C., and the remaining ethylene is introduced from the ethylene feed port. Further, it is preferable that the catalyst feed port, the ethylene feed port, and the hexane feed port in which ethylene is dissolved are all provided at the bottom of the reactor, and all of them are introduced into the reactor at the same time.

(Additive)
Additives such as a slip agent, a neutralizing agent, an antioxidant, a light-resistant stabilizer, an antistatic agent, and a pigment are added to the ethylene-based polymer contained in the polyethylene resin composition of the present embodiment, if necessary. be able to.

The slip agent or neutralizing agent is not particularly limited, and examples thereof include aliphatic hydrocarbons, higher fatty acids, higher fatty acid metal salts, fatty acid esters of alcohols, waxes, higher fatty acid amides, silicone oils, and rosins. The content of the slip agent or the neutralizing agent is not particularly limited, but is preferably 5000 ppm or less, more preferably 4000 ppm or less, and further preferably 3000 ppm or less.

The antioxidant is not particularly limited, but for example, a phenol-based compound or a phenol-phosphoric acid-based compound is preferable. Specifically, 2,6-di-t-butyl-4-methylphenol (dibutylhydroxytoluene), n-octadecyl-3- (4-hydroki-3,5-di-t-butylphenyl) propionate, tetrakis. (Methylene (3,5-di-t-butyl-4-hissaroxyhydrocin namemate)) Phenolic antioxidants such as methane; 6- [3- (3-t-butyl-4-hydroxy-5-methyl) Phenyl) propoxy] -2,4,8,10-tetra-t-butyldibenzo [d, f] [1,3,2] Phenolline-based antioxidants such as dioxaphosphepine; tetrakis (2,4) -Di-t-butylphenyl) -4,4'-biphenylene-di-phosphonite, tris (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,4-t-) Butylphenylphosphite) and other phosphorus-based antioxidants can be mentioned.

In the ethylene polymer contained in the polyethylene resin composition of the present embodiment, the amount of the antioxidant is preferably 5 parts by mass or less when the total of the polyethylene resin composition and the liquid paraffin is 100 parts by mass. Yes, more preferably 4 parts by mass or less, further preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less. When the amount of the antioxidant is 5 parts by mass or less, the deterioration of polyethylene is suppressed, embrittlement, discoloration, deterioration of mechanical properties and the like are less likely to occur, and the long-term stability is improved.

The light-resistant stabilizer is not particularly limited, and is, for example, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chloro. Benzotriazole-based light-resistant stabilizers such as benzotriazole; bis (2,2,6,6-tetramethyl-4-piperidin) sebacate, poly [{6- (1,1,3,3-tetramethylbutyl) amino- 1,3,5-triazin-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-) Examples thereof include hindered amine-based light-resistant stabilizers such as piperidine) imino}]. The content of the light-resistant stabilizer is not particularly limited, but is preferably 5000 ppm or less, more preferably 3000 ppm or less, and further preferably 2000 ppm or less.

The antistatic agent is not particularly limited, and examples thereof include aluminosilicate, kaolin, clay, natural silica, synthetic silica, silicates, talc, diatomaceous earth, and the like, and glycerin fatty acid ester.

[Use of polyethylene resin composition]
The polyethylene resin composition of the present embodiment can be used for various purposes. For example, it is suitable as a microporous membrane for a secondary battery separator, particularly a microporous membrane for a lithium ion secondary battery separator, a sintered body, a high-strength fiber, or the like.
Examples of the method for producing a microporous membrane include a method in which a wet method using a solvent is carried out by extruding, stretching, extracting and drying with an extruder equipped with a T-die. In addition, by taking advantage of the excellent features such as wear resistance, high sliding property, high strength, and high impact resistance, which are the characteristics of high molecular weight ethylene polymer, it is possible to obtain a molded product obtained by sintering an ethylene polymer. Can also be used.

Hereinafter, the present embodiment will be described in more detail with reference to specific examples and comparative examples, but the present invention is not limited to the following examples and comparative examples.

[Measurement method and conditions]
The physical characteristics of the polyethylene resin compositions of Examples and Comparative Examples were measured by the following methods.

(1) Measurement of molecular weight Using the polyethylene resin composition and the extracted component obtained in (3) described later as a measurement sample, 15 mL of o-dichlorobenzene was introduced into 20 mg of the measurement sample, and the mixture was stirred at 150 ° C. for 1 hour. A sample solution was prepared, and gel permeation chromatography (GPC) was measured under the following conditions.
From the measurement results, the number average molecular weight (Mn), the weight average molecular weight (Mw), and the molecular weight distribution (Mw / Mn) were determined based on a calibration curve prepared using commercially available monodisperse polystyrene.
-Device: Waters 150-C ALC / GPC
-Detector: RI detector-Mobile phase: o-dichlorobenzene (for high performance liquid chromatograph)
-Flow rate: 1.0 mL / min-Column: One AT-807S manufactured by Shodex and two TSK-gelGMH-H6 manufactured by Tosoh were connected.
-Column temperature: 140 ° C

(2) CFC elution amount (TREF elution amount)
<Condition 1>
Using the extracted component obtained in (3) described later as a measurement sample, cross-separation chromatography (CFC) measurement was performed on the о-dichlorobenzene solution of the measurement sample, and the elution temperature-elution amount curve was measured as follows. The elution amount at each temperature, the temperature at which the CFC elution amount reaches the maximum value (° C.), and the temperature at which the integrated elution amount in the CFC measurement reaches 10% by mass (° C.) were determined.
First, the temperature of the column containing the filler was raised to 140 ° C., a sample solution in which the measurement sample was dissolved in o-dichlorobenzene was introduced, and the sample was held for 120 minutes.
Next, the temperature of the column was lowered to 40 ° C. at a temperature lowering rate of 0.5 ° C./min and then held for 20 minutes to precipitate the sample on the filler surface.

Then, the temperature of the column was sequentially raised at a heating rate of 20 ° C./min.
First, the temperature is raised from 40 ° C to 60 ° C at 10 ° C intervals, from 60 ° C to 69 ° C at 3 ° C intervals, from 69 ° C to 100 ° C at 1 ° C intervals, and from 100 ° C to 120 ° C. The temperature was raised at 10 ° C. intervals. After maintaining the temperature for 21 minutes at each temperature, the temperature was raised to detect the concentration of the sample (ethylene-based polymer) eluted at each temperature. Then, the elution temperature-elution amount curve is measured from the values of the elution amount (mass%) of the sample (ethylene-based polymer) and the in-column temperature (° C.) at that time, and the elution amount and the integrated elution amount at each temperature are measured. , The temperature at which the elution amount in the CFC measurement became the maximum value (° C.), and the temperature at which the integrated elution amount in the CFC measurement reached 10% by mass (° C.) were determined.
-Device: Polymer ChaAR's Automated 3D analyzer CFC-2
-Column: Stainless steel micro ball column (3/8 "od x 150 mm)
-Eluent: o-dichlorobenzene (for high performance liquid chromatography)
-Sample solution concentration: Sample (ethylene polymer) 20 mg / o-dichlorobenzene 20 mL
・ Injection volume: 0.5 mL
-Pump flow rate: 1.0 mL / min-Detector: Polymer ChAR infrared spectrophotometer IR4
-Detected wave number: 3.42 μm
-Sample dissolution conditions: 140 ° C x 120 min dissolution

<Condition 2>
Using the polyethylene resin composition as a measurement sample, the elution temperature-elution amount curve by temperature elution fractionation (TREF) was measured for the measurement sample as follows, and the elution amount at each temperature, the integrated elution amount, and CFC. The temperature (° C.) at which the elution amount in the measurement reaches the maximum value (Max) was determined, and the number of peaks in the CFC measurement was determined.
First, the temperature of the column containing the filler was raised to 140 ° C., a sample solution in which the measurement sample was dissolved in o-dichlorobenzene was introduced, and the sample was held for 120 minutes. Next, the temperature of the column was lowered to 40 ° C. at a temperature lowering rate of 0.5 ° C./min and then held for 20 minutes to precipitate the sample on the filler surface.

Then, the temperature of the column was sequentially raised at a heating rate of 20 ° C./min.
First, the temperature is raised from 40 ° C to 60 ° C at 10 ° C intervals, from 60 ° C to 75 ° C at 5 ° C intervals, from 75 ° C to 90 ° C at 3 ° C intervals, and from 90 ° C to 110 ° C. The temperature was raised at 1 ° C. intervals, and from 110 ° C. to 120 ° C. at 5 ° C. intervals. After maintaining the temperature for 21 minutes at each temperature, the temperature was raised to detect the concentration of the sample (ethylene-based polymer) eluted at each temperature. Then, the elution temperature-elution amount curve is measured from the values of the elution amount (mass%) of the sample (ethylene-based polymer) and the in-column temperature (° C.) at that time, and the elution amount and the integrated elution amount at each temperature are measured. , And the temperature (° C.) at which the elution amount in the CFC measurement reaches the maximum value (Max) was determined, and the number of peaks in the CFC measurement was determined.
-Device: Polymer ChaAR's Automated 3D analyzer CFC-2
-Column: Stainless steel micro ball column (3/8 "od x 150 mm)
-Eluent: o-dichlorobenzene (for high performance liquid chromatography)
-Sample solution concentration: Sample (ethylene polymer) 20 mg / o-dichlorobenzene 20 mL
・ Injection volume: 0.5 mL
-Pump flow rate: 1.0 mL / min-Detector: Polymer ChAR infrared spectrophotometer IR4
-Detected wave number: 3.42 μm
-Sample dissolution conditions: 140 ° C x 120 min dissolution

(3) Temperature-increasing free fractionation Temperature-increasing free fractionation is a method of dissolving and extracting a solvent-soluble target component from a sample using a general Soxhlet extractor.
A Soxhlet extractor is a device with a heater and solvent container at the bottom, a filter paper containing a sample in the middle, and a cooling tube at the top.
When the container containing the solvent is heated, the solvent evaporates, is cooled by the uppermost cooling tube, drips into the sample, dissolves a small amount of the solvent-soluble component, and then returns to the container containing the solvent. Since the solvent-soluble component has a higher boiling point than the solvent, by repeating this cycle, the solvent-soluble component (extract component) is gradually concentrated in the container containing the solvent, and the solvent-insoluble component (residue) is contained in the filter paper. ) Remains.
Toluene was used as the solvent, and the extraction operation was carried out at a temperature equal to or higher than the boiling point for 6 hours.
Then, in order to collect the extracted component extracted in the toluene solvent, methanol was put in the toluene solvent, reprecipitated, and suction filtered to obtain the extracted component.

(4) Melting point (Tm)
Using a differential scanning calorimeter (DSC-7 type device manufactured by PerkinElmer Co., Ltd.), the melting point of the extracted component obtained in (3) above was measured under the conditions 1) to 3) below. 1) About 5 mg of the measurement sample was packed in an aluminum pan, heated to 200 ° C. at 200 ° C./min, and held at 200 ° C. for 5 minutes. 2) Next, the temperature was lowered from 200 ° C. to 50 ° C. at a temperature lowering rate of 10 ° C./min, and the temperature was maintained for 5 minutes after the temperature reduction was completed. 3) Next, the temperature was raised from 50 ° C. to 200 ° C. at a heating rate of 10 ° C./min. From the endothermic curve observed in the process of 3) above, the maximum temperature at the melting peak position was defined as the melting point (° C.).

(5) Lamella thickness of the extracted component The lamella thickness of the extracted component obtained in (3) above was measured by wide-angle X-ray scattering (WAXS) under the following conditions.
For the measurement, Ultima-IV manufactured by Rigaku Co., Ltd. was used.
Cu-Kα rays were incident on the powder of the ethylene polymer which is the extraction component of the sample, and the diffracted light was detected by D / tex Uitra.
The measurement conditions were that the distance between the sample and the detector was 285 mm, the excitation voltage was 40 kV, and the current was 40 mA. A centralized optical system was adopted as the optical system, and the slit conditions were DS = 1/2 °, SS = open, and vertical slit = 10 mm.

(6) Ti, Al content in the sample A polyethylene resin composition or the extracted component obtained in (3) above is used as a measurement sample, and the measurement sample is used as a microwave decomposition apparatus (model ETHOS TC, manufactured by Milestone General Co., Ltd.). Inductively coupled plasma mass spectrometer, model X series X7, manufactured by Thermo Fisher Scientific Co., Ltd., Ti, Al elements as metals in the sample by internal standard method. The concentration was measured.

(7) Comonomer content (content of α-olefin unit)
The content (mol%) of the polymerization unit derived from the α-olefin in the extract component obtained in (3) above was measured by G.I. J. This was performed according to the method disclosed in Macromolecules, 10, 773 (1977) of Ray et al. The content of the α-olefin unit was calculated from the area intensity of the methylene carbon signal observed by the ^{13 C-NMR spectrum.}
Measuring device: JEOL ECS-400
Observation nucleus: ¹³ C
Observation frequency: 100.53 MHz
Pulse width: 45 ° (7.5 μsec)
Pulse program: single pulse dec
PD: 5 sec
Measurement temperature: 130 ° C
Number of integrations: 30,000 times or more Reference: PE (-eeee-) signal, 29.9 ppm
Solvent: o-dichlorobenzene-d4
Sample concentration: 5-10% by mass
Melting temperature: 130-140 ° C

(8) Method for Producing Polyethylene Resin Composition When the total of the ethylene-based polymer and liquid paraffin produced in Examples and Comparative Examples described later is 100 parts by mass, 30 to 40 parts by mass of the ethylene-based polymer is obtained. 60 to 70 parts by mass of liquid paraffin (liquid paraffin manufactured by Matsumura Petroleum Research Institute Co., Ltd. (product name: Smoyl P-350P)) and 1 part by mass of antioxidant (Great Lakes Chemical Japan Co., Ltd. Tetrakiss [ Methane (3,5-di-t-butyl-4-hydroxy-hydrosinamate)] methane (product name: ANOX20)) was blended to prepare a slurry-like liquid.
After substituting the obtained slurry liquid with nitrogen, feed it to a twin-screw extruder (main body model: 2D25S) for a lab plast mill (main body model: 30C150) manufactured by Toyo Seiki Co., Ltd. in a nitrogen atmosphere. After being charged through and kneaded at 200 ° C., extruded from a T-die installed at the tip of the extruder, and immediately cooled and solidified with a cast roll cooled to 25 ° C. to form a gel-like sheet.
This gel-like sheet was stretched 7 × 7 times at 120 ° C. using a simultaneous biaxial stretching machine, and then the stretched film was immersed in methyl ethyl ketone or hexane to extract and remove liquid paraffin, and then vacuum dried for 24 hours or more.
Further, it was heat-fixed at 125 ° C. for 3 minutes to obtain a polyethylene resin composition in the form of a microporous film.

(9) Fuse performance The fuse performance of the microporous polyethylene resin composition formed by the method described in (8) above is that the polyethylene resin composition is impregnated with an electrolytic solution and sandwiched between SUS plate electrodes. A cell having a configuration was prepared and evaluated by measuring the AC resistance of the cell while raising the temperature. The temperature at which the resistance value suddenly increased was defined as the fuse temperature (° C.), and the evaluation was performed with the number of measurements n = 5, and the average value was calculated. The evaluation criteria are as follows.
(Evaluation criteria)
◎ (Good): Less than 132 ℃ ○ (Normal): 132 ℃ or more and less than 135 ℃ × (Bad): 135 ℃ or more

(10) Fuse speed The fuse speed of the microporous polyethylene resin composition formed by the method described in (8) above is such that the polyethylene resin composition is impregnated with an electrolytic solution and sandwiched between SUS plate electrodes. A cell having a plastic structure was prepared and evaluated by measuring the AC resistance of the cell while raising the temperature. A rapid increase in resistance was confirmed near the melting point of the polyethylene resin composition (fuse performance), and the time from the start of the increase in resistance to the arrival at the maximum resistance value (seconds) was evaluated. The evaluation was performed with the number of measurements n = 5, and the average value was calculated as the fuse speed. The evaluation criteria are as follows.
(Evaluation criteria)
◎ (Good): Less than 5 seconds ○ (Normal): 5 seconds or more and less than 10 seconds × (Bad): 10 seconds or more

(11) Puncture strength A needle was applied to the microporous polyethylene resin composition formed by the method described in (8) above using a Kato Tech product "KES-G5 Handy Compression Tester" (trademark). A piercing test was performed under the conditions of a radius of curvature of the tip of 0.5 mm and a piercing speed of 2 mm / sec, and the maximum piercing load (N) was measured. When the maximum piercing load (N) is 3.5 N or more, it indicates that the strength is sufficiently excellent. The evaluation was performed with the number of measurements n = 10, and the average value was calculated as the puncture strength. The evaluation criteria are as follows.
(Evaluation criteria)
◎ (Good): 3.5N or more ○ (Normal): 3.0N or more and less than 3.5N × (Bad): Less than 3.0N

(12) Number of Film Defects Defects existing in 250 mm × 250 mm of the microporous polyethylene resin composition formed by the method described in (8) above (when the film is observed with transmitted light, it is observed as black spots. (Excluding impurities such as dust) was visually counted. Based on the number obtained, defects were evaluated according to the following evaluation criteria. The evaluation was performed with the number of measurements n = 10, and the average value was calculated as the number of film defects. The evaluation criteria are as follows.
(Evaluation criteria)
◎ (Good): 10 or less ○ (Normal): 11 or more and 20 or less × (Bad): 21 or more

(13) Film thickness unevenness The film thickness of the microporous polyethylene resin composition formed by the method described in (8) above was measured using a microthickening instrument (type KBM (registered trademark)) manufactured by Toyo Seiki. Was measured at room temperature. Arbitrary 10 places were selected and measured so as to be evenly evenly distributed for each 1 m of the film, and a total of 50 places of 5 m of the film were measured to calculate the average film thickness. The average film thickness was 5 μm or more and 30 μm or less.
(Evaluation criteria)
◎ (Good): Variation of less than ± 3 μm with respect to average film thickness 〇 (Normal): Variation of ± 3 μm or more and less than 5 μm with respect to average film thickness × (Bad): Variation of ± 5 μm or more with respect to average film thickness

[Catalyst synthesis method]
(Production Example 1: Catalyst Synthesis Example 1: Preparation of Solid Catalyst Component [A])
(1) Synthesis of raw material (a-1) _{2,000 mL of 1 mol / L Mg 6} (C ₄ H ₉ ) ₁₂ AL (C ₂ H ₅ ) ₃ hexane solution in a fully nitrogen-substituted 8 L stainless steel autoclave ( (Equivalent to 2000 mmol of magnesium and aluminum) was charged, and 146 mL of a 5.47 mol / L n-butanol hexane solution was added dropwise over 3 hours while stirring at 50 ° C., and the line was washed with 300 mL of hexane after completion. Further, stirring was continued at 50 ° C. for 2 hours. After completion of the reaction, the raw material (a-1) was cooled to room temperature. The raw material (a-1) had a magnesium concentration of 0.704 mol / L.
(2) Synthesis of raw material (a-2) 2,000 mL _{of 1 mol / L Mg 6} (C ₄ H ₉ ) ₁₂ AL (C ₂ H ₅ ) _{3 hexane solution in an 8 L stainless steel autoclave fully substituted with nitrogen (} (Equivalent to 2000 mmol of magnesium and aluminum) was charged, and while stirring at 80 ° C., 240 mL of a hexane solution of 8.33 mol / L methylhydrodienepolysiloxane (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was pumped, and further at 80 ° C. over 2 hours. Stirring was continued. After completion of the reaction, the raw material (a-2) was cooled to room temperature. The raw material (a-2) had a total concentration of magnesium and aluminum of 0.786 mol / L.
(3) Synthesis of (A-1) Carrier In an 8 L stainless steel autoclave fully substituted with nitrogen, 1,000 mL of a hexane solution of 1 mol / L hydroxytrichlorosilane was charged, and the organic magnesium of the raw material (a-1) was charged at 65 ° C. 1340 mL of a hexane solution of the compound (equivalent to 943 mmol of magnesium) was added dropwise over 3 hours, and the reaction was continued with stirring at 65 ° C. for 1 hour. After completion of the reaction, the supernatant was removed and washed 4 times with 1,800 mL of hexane to obtain a carrier (A-1). As a result of analyzing this carrier, the amount of magnesium contained in 1 g of the solid was 7.5 mmol.
(4) Preparation of Solid Catalyst Component [A] While stirring 1,970 mL of the hexane slurry containing 110 g of the carrier (A-1) at 10 ° C., 103 mL of a 1 mol / L titanium tetrachloride hexane solution and a raw material (a). -2) 131 mL was added simultaneously over 3 hours. After the addition, the reaction was continued at 10 ° C. for 1 hour. After completion of the reaction, the supernatant was removed and washed with hexane four times to remove the unreacted raw material component, and the solid catalyst component [A] was prepared.

(Production Example 2: Catalyst synthesis Example 2: Preparation of supported metallocene catalyst component [B])
(1) Synthesis of raw material [b-1] Spherical silica having an average particle size of 7 μm, a surface area of 700 m ² / g, and an intraparticle pore volume of 1.9 mL / g is calcined at 500 ° C. for 5 hours in a nitrogen atmosphere. And dehydrated.
In a nitrogen atmosphere, 40 g of this dehydrated silica was dispersed in 800 mL of hexane in an autoclave having a capacity of 1.8 L to obtain a slurry.
While keeping the obtained slurry at 20 ° C. under stirring, 100 mL of a hexane solution of triethylaluminum (concentration 1 mol / L) was added dropwise over 1 hour, and then the mixture was stirred at the same temperature for 2 hours.
Then, unreacted triethylaluminum in the supernatant was removed by decantation in the obtained reaction mixture. In this way, 800 mL of a hexane slurry of the raw material [b-1], which is a silica component treated with triethylaluminum, was obtained.
(2) Preparation of raw material [b-2] [(N-t-butylamide) (tetramethyl-η5-cyclopentadienyl) dimethylsilane] Titanium-1,3-pentadiene (hereinafter referred to as "titanium complex"). .) 200 mmol was dissolved in 1250 mL of Isopar E [trade name of hydrocarbon mixture manufactured by Exxon Chemical Co., Ltd. (USA)], 40 mL of a commercially available 1 mol / L hexane solution of butylethylmagazine was added, and hexane was further added to concentrate the titanium complex. Was adjusted to 0.1 mol / L to obtain a raw material [b-2].
(3) Preparation of Raw Material [b-3] 5.7 g of bis (taroalkyl hydride) methylammonium-tris (pentafluorophenyl) (4-hydroxyphenyl) borate (hereinafter referred to as "borate") is added to toluene. It was added to 50 mL and dissolved to obtain a 100 mmol / L toluene solution of borate. To a toluene solution of this borate, 5 mL of a 1 mol / L hexane solution of ethoxydiethylaluminum was added at room temperature, and hexane was further added so that the borate concentration in the solution became 70 mmol / L. Then, the mixture was stirred at room temperature for 1 hour to obtain a raw material [b-3] which is a reaction mixture containing borate.
(4) Preparation of Supported Metallocene Catalyst [B] Titanium obtained in (2) above while stirring 800 mL of the raw material [b-1] slurry which is the silica component obtained in (1) above at 20 ° C. 32 mL of the complex raw material [b-2] and 46 mL of the reaction mixture raw material [b-3] containing the borate obtained in (3) above were added at the same time for 1 hour, and further at the same temperature. The mixture was stirred for 1 hour to react the titanium complex with the borate. After completion of the reaction, the supernatant is removed, and the unreacted catalyst raw material is removed with hexane to form a supported metallocene catalyst [B] (hereinafter, solid catalyst component [B] in which the catalytically active species is formed on the silica. ]) Was obtained.

[Example 1]
(Polymerization step of ethylene polymer (A-1))
Hexane, ethylene, 1-butene, hydrogen and catalyst were continuously supplied to a Vessel-type 300L polymerization reactor equipped with a stirrer. The polymerization pressure was 0.5 MPa. The polymerization temperature was maintained at 78 ° C. by cooling the jacket. Hexane was prepared as ethylene-dissolved hexane in which ethylene gas was previously pressurized at 0.2 MPa, adjusted to 3 ° C., and supplied from the bottom of the polymerizer at 40 L / hr.
The remaining ethylene was supplied from the bottom of the polymerizer so as to keep the polymerization pressure at 0.5 MPa.
In addition, 1-butene was introduced from a 5 mol% vapor phase with respect to ethylene. The solid catalyst component [A] and triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were used as co-catalysts. The solid catalyst component [A] is supplied from the bottom of the polymerizer at a feed rate of 2.0 m / s and 0.2 g / hr while being maintained at 3 ° C., and triisobutylaluminum is supplied at a rate of 10 mmol / hr. Supplied from the bottom of the polymerizer.
The catalyst / ethylene / hexane were all fed at the same time.
The production rate of the ethylene polymer was 10 kg / hr.
Further, hydrogen was continuously supplied by a pump so that the hydrogen concentration with respect to ethylene in the gas phase was 35 mol%. Hydrogen was supplied from the catalyst introduction line in advance for contact with the catalyst. The catalytic activity was 80,000 g-PE / g-solid catalytic component [A]. The polymer slurry was continuously drawn through a flash drum at a pressure of 0.05 MPa and a temperature of 70 ° C. so that the level of the polymerization reactor was kept constant, and unreacted ethylene and hydrogen were separated.

Next, the polymer slurry was continuously sent to a centrifuge so that the level of the polymerization reactor was kept constant, and the ethylene-based polymer and other solvents and the like were separated. The content of the solvent and the like with respect to the polymer at that time was 45% by mass.

The separated ethylene polymer was dried while blowing nitrogen at 85 ° C. In this drying step, steam was sprayed onto the ethylene polymer powder to deactivate the catalyst and co-catalyst. An ethylene polymer (A-1) was obtained by removing the obtained ethylene polymer powder that did not pass through the sieve using a sieve having a mesh size of 425 μm. The density was 947 kg / m ³ and the MFR was 5 g / 10 min.

(Polymerization step of ethylene polymer (B-1))
Hexane, ethylene, hydrogen and catalyst were continuously supplied to a Vessel-type 300L polymerization reactor equipped with a stirrer. The polymerization pressure was 0.5 MPa. The polymerization temperature was maintained at 85 ° C. by jacket cooling. Hexane was supplied from the bottom of the polymerizer at 40 L / hr. The solid catalyst component [A] and triisobutylaluminum were used as co-catalysts. The solid catalyst component [A] was added at a rate of 0.2 g / hr from the middle of the liquid surface and the bottom of the polymer, and triisobutylaluminum was added at a rate of 10 mmol / hr from the middle of the liquid surface and the bottom of the polymer. .. The solid catalyst component [A] and the co-catalysts triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were alternately charged intermittently, and adjusted so that they would come into contact with each other at the moment when they were charged into the reactor. The production rate of the ethylene polymer was 10 kg / hr. Hydrogen was continuously pumped so that the hydrogen concentration in the gas phase with respect to ethylene was 5.5 mol%. Hydrogen was supplied from the catalyst introduction line in advance for contact with the catalyst, and ethylene was supplied from the bottom of the polymerizer. The catalytic activity was 80,000 g-PE / g-solid catalytic component [A]. The polymer slurry was continuously drawn through a flash drum at a pressure of 0.05 MPa and a temperature of 70 ° C. so that the level of the polymerization reactor was kept constant, and unreacted ethylene and hydrogen were separated.

Next, the polymer slurry was continuously sent to a centrifuge so that the level of the polymerization reactor was kept constant, and the ethylene-based polymer and other solvents and the like were separated. At that time, the content of the solvent and the like with respect to the ethylene polymer was 45% by mass.

The separated ethylene polymer was dried while blowing nitrogen at 85 ° C. In this drying step, steam was sprayed onto the ethylene polymer powder to deactivate the catalyst and co-catalyst. To the obtained ethylene polymer powder, 500 ppm of calcium stearate (manufactured by Dainichi Chemical Co., Ltd., C60) was added, and the mixture was uniformly mixed using a Henschel mixer. An ethylene polymer (B-1) was obtained by removing the obtained ethylene polymer powder that did not pass through the sieve using a sieve having a mesh size of 425 μm. The weight average molecular weight of 70 × 10 ^4.

(Manufacturing method of polyethylene resin composition)
A total of 100 parts by mass of the ethylene-based polymer (A-1) and the ethylene-based polymer (B-1) (75 parts by mass of (A-1) and 25 parts by mass of (B-1)), and an antioxidant. Polyethylene powder by adding 0.3 parts by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and dry-blending using a tumbler blender. A mixture was obtained.
The obtained polyethylene powder mixture was replaced with nitrogen and then charged into a twin-screw extruder through a feeder under a nitrogen atmosphere.
Further, 65 parts by mass of liquid paraffin (P-350 (trademark) manufactured by Matsumura Oil Co., Ltd.) is injected into the extruder by side feed, kneaded at 200 ° C., extruded from the T die installed at the tip of the extruder, and then extruded. Immediately, it was cooled and solidified with a cast roll cooled to 25 ° C. to form a gel-like sheet having a thickness of 1500 μm.
This gel-like sheet was stretched 7 × 7 times at 120 ° C. using a simultaneous biaxial stretching machine, and then the stretched film was immersed in methylene chloride to extract and remove liquid paraffin, and then dried.
Next, it was re-stretched 1.2 × 1.2 times and then heat-treated to obtain a polyethylene resin composition in the form of a microporous film. The measurement and evaluation results are shown in Table 1.

[Example 2]
(Polymerization step of ethylene polymer (A-2))
In the polymerization step, the hydrogen concentration was set to 45 mol%, and 1-butene was introduced from the vapor phase of 6 mol% with respect to ethylene by the same operation as that of the ethylene polymer (A-1) in Example 1. An ethylene polymer (A-2) was obtained. The density was 947 kg / m ³ and the MFR was 10 g / 10 min. Further, in the polyethylene resin composition in the form of a microporous film of Example 2, an ethylene-based polymer (A-2) and an ethylene-based polymer (B-1) were used (75 parts by mass of (A-2)). It was obtained by the same operation as in Example 1 except that (B-1) was 25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 3]
(Polymerization step of ethylene polymer (A-3))
In the polymerization step, the hydrogen concentration was set to 50 mol%, 1-butene was introduced from the vapor phase of 7.5 mol% with respect to ethylene, the temperature of ethylene-dissolved hexane was adjusted to 4 ° C., and the mixture was supplied from the side surface of the polymerizer. The ethylene-based polymer (A-1) was subjected to the same operation as that of the ethylene-based polymer (A-1) in Example 1 except that the catalyst temperature was adjusted to 4 ° C. and the mixture was supplied from the middle between the liquid level and the bottom of the polymerizer. A-3) was obtained. The density was 947 kg / m ³ and the MFR was 30 g / 10 min.
Further, in the polyethylene resin composition in the form of a microporous film of Example 3, an ethylene-based polymer (A-3) and an ethylene-based polymer (B-1) were used (75 parts by mass of (A-3)). It was obtained by the same operation as in Example 1 except that (B-1) was 25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 4]
(Polymerization step of ethylene polymer (A-4))
_{In the polymerization step, 1 mol / L Mg 6} (C ₄ H ₉ ) ₁₂ AL (C ₂ H ₅ ) ₃ was used in an 8 L stainless steel autoclave sufficiently nitrogen-substituted as a co-catalyst using the supported metallocene catalyst component [B]. 2,000 mL of hexane solution (equivalent to 2000 mmol of magnesium and aluminum) was charged, and 240 mL of a hexane solution of 8.33 mol / L methylhydrodiene polysiloxane (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was pumped while stirring at 80 ° C. Examples except that the mixture was cooled to room temperature after continuing stirring at 80 ° C. for 2 hours, the hydrogen concentration was 30 mol%, and 1-butene was introduced from the 8 mol% vapor phase with respect to ethylene. An ethylene polymer (A-4) was obtained by the same operation as that of the ethylene polymer (A-1) in 1. The density was 941 kg / m ³ and the MFR was 2.5 g / 10 min. Further, in the polyethylene resin composition in the form of a microporous film of Example 4, an ethylene-based polymer (A-4) and an ethylene-based polymer (B-1) were used (75 parts by mass of (A-4)). (B-1) was obtained by the same operation as in Example 1 except that 25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 5]
(Polymerization step of ethylene polymer (A-5))
_{In the polymerization step, 1 mol / L Mg 6} (C ₄ H ₉ ) ₁₂ AL (C ₂ H ₅ ) ₃ was used in an 8 L stainless steel autoclave sufficiently nitrogen-substituted as a co-catalyst using the supported metallocene catalyst component [B]. 2,000 mL of hexane solution (equivalent to 2000 mmol of magnesium and aluminum) was charged, and 240 mL of a hexane solution of 8.33 mol / L methylhydrodiene polysiloxane (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was pumped while stirring at 80 ° C. Examples except that the mixture was cooled to room temperature after continuing stirring at 80 ° C. for 2 hours, the hydrogen concentration was 35 mol%, and 1-butene was introduced from the 9 mol% vapor phase with respect to ethylene. The ethylene-based polymer (A-5) was obtained by the same operation as that of the ethylene-based polymer (A-1) in 1. The density was 941 kg / m ³ and the MFR was 5 g / 10 min. Further, in the polyethylene resin composition in the form of a microporous film of Example 5, an ethylene-based polymer (A-5) and an ethylene-based polymer (B-1) were used (75 parts by mass of (A-5)). It was obtained by the same operation as in Example 1 except that (B-1) was 25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 6]
(Polymerization step of ethylene polymer (A-6))
In the polymerization step, except that the hydrogen concentration was set to 40 mol%, 1-butene was introduced from the vapor phase of 11 mol% with respect to ethylene, the temperature of ethylene-dissolved hexane was adjusted to 4 ° C, and the catalyst temperature was adjusted to 25 ° C. , The ethylene-based polymer (A-6) was obtained by the same operation as that of the ethylene-based polymer (A-1) in Example 1. The density was 941 kg / m ³ and the MFR was 10 g / 10 min. Further, in the polyethylene resin composition in the form of a microporous film of Example 6, an ethylene-based polymer (A-6) and an ethylene-based polymer (B-1) were used (75 parts by mass of (A-6)). It was obtained by the same operation as in Example 1 except that (B-1) was 25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 7]
(Polymerization step of ethylene polymer (A-7))
In the polymerization step, ethylene-dissolved hexane was adjusted to 25 ° C. and supplied from the side surface of the polymerizer, and the catalyst was kept at 25 ° C. and supplied from the middle of the liquid surface and the bottom of the polymerizer at a feed linear velocity of 3.5 m / s. The co-catalyst is supplied from the middle between the liquid surface and the bottom of the polymer, the catalyst and the ethylene-dissolved hexane are supplied in three places from the bottom of each polymer, and the catalyst / ethylene / hexane feed is simultaneously. An ethylene-based polymer (A-7) was obtained by the same operation as that of the ethylene-based polymer (A-1) in Example 1 except that the polymer was not present. The density was 947 kg / m ³ and the MFR was 5 g / 10 min.
(Polymerization step of ethylene polymer (B-2))
_{In the polymerization step, 1 mol / L Mg 6} (C ₄ H ₉ ) ₁₂ AL (C ₂ H ₅ ) was used in an 8 L stainless steel autoclave sufficiently nitrogen-substituted as a co-catalyst using the supported metallocene catalyst component [B]. It was charged (2000 mmol corresponding magnesium and aluminum) ₃ in hexane 2,000 mL, stirring at 80 ° C., pumping a hexane solution 240mL of methylhydrodiene polysiloxane of 8.33mol / L (manufactured by Shin-Etsu Chemical Co., Ltd.), Further, the ethylene-based polymer (B-1) was subjected to the same operation as that of the ethylene-based polymer (B-1) in Example 1 except that the mixture was cooled to room temperature after continuing stirring at 80 ° C. for 2 hours. B-2) was obtained. The weight average molecular weight of 70 × 10 ^4.
Further, in the polyethylene resin composition in the form of a microporous film of Example 7, an ethylene-based polymer (A-7) and an ethylene-based polymer (B-2) were used (75 parts by mass of (A-7)). (B-2) was obtained by the same operation as in Example 1 except that (25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 8]
(Polymerization step of ethylene polymer (A-8))
In the polymerization step, the hydrogen concentration was set to 30 mol%, 1-butene was introduced from the 8 mol% vapor phase with respect to ethylene, ethylene-dissolved hexane was adjusted to 25 ° C. and supplied from the side of the polymer, and the catalyst was supplied from the side of the polymer. The co-catalyst is supplied from the middle between the liquid surface and the bottom, the co-catalyst is supplied from the middle between the liquid surface and the bottom of the polymer, and the catalyst and the ethylene-dissolved hexane are supplied from the bottom of each polymer in three places. The ethylene-based polymer (A-8) was obtained by the same operation as that of the ethylene-based polymer (A-1) in Example 1 except that the catalyst / ethylene / hexane feeds were not simultaneous. The density was 941 kg / m ³ and the MFR was 2.5 g / 10 min.
Further, in the polyethylene resin composition in the form of a microporous film of Example 8, an ethylene-based polymer (A-8) and an ethylene-based polymer (B-2) were used (75 parts by mass of (A-8)). (B-2) was obtained by the same operation as in Example 1 except that (25 parts by mass). The measurement and evaluation results are shown in Table 1.

[Example 9]
(Polymerization step of ethylene polymer (B-3))
In the polymerization step, an ethylene-based polymer (B-3) was obtained by the same operation as that of the ethylene-based polymer (B-1) in Example 1 except that the polymerization temperature was adjusted to 78 ° C. The weight average molecular weight of 100 × 10 ^4.
Further, the microporous polyethylene resin composition of Example 9 uses an ethylene-based polymer (A-2) and an ethylene-based polymer (B-3), and uses 65 mass of the ethylene-based polymer (A-2). It was obtained by the same operation as in Example 1 except that the total amount was 100 parts by mass of the part and 35 parts by mass of the ethylene polymer (B-3). The measurement and evaluation results are shown in Table 1.

[Example 10]
(Polymerization step of ethylene polymer (B-4))
In the polymerization step, an ethylene-based polymer (B-4) was obtained by the same operation as that of the ethylene-based polymer (B-1) in Example 1 except that the polymerization temperature was adjusted to 75 ° C. The weight average molecular weight of 200 × 10 ^4.
Further, the microporous polyethylene resin composition of Example 10 uses an ethylene-based polymer (A-2) and an ethylene-based polymer (B-4), and uses 65 mass of the ethylene-based polymer (A-2). It was obtained by the same operation as in Example 1 except that the total amount was 100 parts by mass of the part and 35 parts by mass of the ethylene polymer (B-4). The measurements and results are shown in Table 1.

[Example 11]
As shown below, the ethylene-based polymer (A-14) is polymerized in the first-stage reactor, and the ethylene-based polymer (B-8) is polymerized in the second-stage reactor. The ethylene polymer of Example 11 was obtained. The weight average molecular weight of the ethylene polymer of Example 11 was 350,000, and the molecular weight distribution was 18. The measurements and results are shown in Table 1.

(Polymerization step of ethylene polymer (A-14))
The ethylene-based polymer was polymerized using a Vessel-type 300L polymerizer equipped with a stirring blade having three swept blades and three baffle plates. Hexane used as a solvent was adjusted to 3 ° C. as ethylene-dissolved hexane in which ethylene gas was previously pressurized at 0.2 MPa and supplied from the bottom of the polymer at a flow rate of 40 L / hr, and the stirring speed was 230 rpm. The remaining ethylene was supplied from the bottom of the polymerizer so as to keep the polymerization pressure at 0.5 MPa. As the polymerization catalyst, the solid catalyst component [A] was used, and as a co-catalyst, triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were used. The solid catalyst component [A] is supplied from the bottom of the polymerizer at a feed rate of 2.0 m / s and 0.2 g / hr while being maintained at 3 ° C., and triisobutylaluminum is supplied at a rate of 10 mmol / hr. Supplied from the bottom of the polymerizer.
The catalyst / ethylene / hexane were all fed at the same time.
Hydrogen was supplied in an amount of 44 mol% (molar ratio: hydrogen / (ethylene + hydrogen + 1-butene)). The polymerization temperature was 78 ° C., the polymerization pressure was 0.65 MPa, the average residence time was 3 hours, and 5.7 mol% (molar ratio: 1-butene / (ethylene + hydrogen + 1-butene)) of 1-butene was supplied as a comonomer. did.
The weight average molecular weight of the ethylene-based polymer (A-14) thus obtained was 60,000. The polymerization activity in the first-stage reactor was 60,000 g per 1 g of the catalyst.
The polymer slurry in the polymer was guided to an intermediate flash tank having a pressure of 0.2 MPa and a temperature of 80 ° C. so that the level in the polymer was kept constant, and unreacted ethylene and hydrogen were separated.

(Polymerization step of ethylene polymer (B-8))
The polymer slurry containing the ethylene-based polymer (A-14) was transferred from the above-mentioned intermediate flash tank to a vessel-type 300L polymerization reactor equipped with a stirring blade having three swept blades and three baffles, and the polymer slurry was transferred. Subsequently, the ethylene-based polymer (B-8) was polymerized. The stirring speed was 200 rpm, and triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were supplied from the bottom of the polymerizer at a rate of 10 mmol / hr as co-catalyst components. Hydrogen is supplied in an amount of 3 mol% (molar ratio: hydrogen / (ethylene + hydrogen + 1-butene)), and 1-butene is supplied as a comonomer in an amount of 1.1 mol% (molar ratio: 1-butene / (ethylene + hydrogen + 1-butene)). did. The polymerization temperature was 78 ° C., the polymerization pressure was 0.30 MPa so that the production rate was 7.0 kg / hr, and the average residence time was 0.85 hours.
The weight average molecular weight of the ethylene-based polymer (B-8) thus obtained was 350,000. The polymerization activity in the second-stage reactor was 8,800 g per 1 g of the catalyst.
The polymer slurry in the polymer was guided to a final flash tank having a pressure of 0.05 MPa and a temperature of 80 ° C. so that the level in the polymer was kept constant, and unreacted ethylene and hydrogen were separated. The average residence time of the final flash tank was 1 hour.
Next, the polymer slurry is continuously sent from the flash tank to the centrifuge by a pump to separate the ethylene-based polymer from the solvent, and then the separated ethylene-based polymer is dried in a rotary kiln type controlled at 85 ° C. It was sent to a machine and dried while blowing nitrogen to obtain an ethylene polymer powder. In this drying step, steam was sprayed on the ethylene polymer to deactivate the catalyst and co-catalyst.

(Manufacturing method of polyethylene resin composition)
To 100 parts by mass of the ethylene polymer powder, 0.3 parts by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] was added as an antioxidant. Then, it was dry-blended using a tumbler blender to obtain an ethylene polymer powder mixture.
The obtained ethylene polymer powder mixture was replaced with nitrogen and then charged into a twin-screw extruder through a feeder under a nitrogen atmosphere.
Further, 65 parts by mass of liquid paraffin (P-350 (trademark) manufactured by Matsumura Petroleum Co., Ltd.) is injected into an extruder by side feed, kneaded at 200 ° C., and extruded from a T die installed at the tip of the extruder. Immediately, it was cooled and solidified with a cast roll cooled to 25 ° C. to form a gel-like sheet having a thickness of 1500 μm.
This gel-like sheet was stretched 7 × 7 times at 120 ° C. using a simultaneous biaxial stretching machine to obtain a stretched film, and the stretched film was immersed in methylene chloride to extract and remove liquid paraffin, and then dried.
Next, it was re-stretched 1.2 × 1.2 times and then heat-treated to obtain a polyethylene resin composition in the form of a microporous film. The measurement and evaluation results are shown in Table 1.

[Comparative Example 1]
(Polymerization step of ethylene polymer (A-9))
Hexane, ethylene, 1-butene, hydrogen and catalyst were continuously supplied to a Vessel-type 300L polymerization reactor equipped with a stirrer. The polymerization pressure was 0.5 MPa. The polymerization temperature was maintained at 78 ° C. by cooling the jacket. Hexane was kept at 25 ° C. as ethylene-dissolved hexane in which ethylene gas was previously pressurized at 0.2 MPa, and was supplied from the side surface of the polymerizer at 40 L / hr. In addition, 1-butene was introduced from a 6 mol% vapor phase with respect to ethylene. The solid catalyst component [A] and triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were used as co-catalysts. The solid catalyst component [A] was kept at 25 ° C. and added at a feed rate of 3.0 m / s and 0.2 g / hr from the middle between the liquid surface and the bottom of the polymer, and triisobutylaluminum was added at a rate of 10 mmol / hr. It was added at a rate from between the liquid level and the bottom of the polymerizer. The production rate of the ethylene polymer was 10 kg / hr. Hydrogen was continuously pumped so that the hydrogen concentration in the gas phase with respect to ethylene was 45 mol%. Hydrogen was supplied from the catalyst introduction line in advance for contact with the catalyst, and ethylene was supplied from the side surface of the polymerizer. The catalytic activity was 80,000 g-PE / g-solid catalytic component [A]. The polymer slurry was continuously drawn through a flash drum at a pressure of 0.05 MPa and a temperature of 70 ° C. so that the level of the polymerization reactor was kept constant, and unreacted ethylene and hydrogen were separated.

Next, the polymer slurry was continuously sent to a centrifuge so that the level of the polymerization reactor was kept constant, and the ethylene-based polymer and other solvents and the like were separated. The content of the solvent and the like with respect to the polymer at that time was 45% by mass.

The separated ethylene polymer was dried while blowing nitrogen at 85 ° C.
In this drying step, steam was sprayed onto the ethylene polymer powder to deactivate the catalyst and co-catalyst. An ethylene polymer (A-9) was obtained by removing the powder of the obtained ethylene polymer that did not pass through the sieve using a sieve having a mesh size of 425 μm. The density was 947 kg / m ³ and the MFR was 10 g / 10 min.

(Polymerization step of ethylene polymer (B-5))
Hexane, ethylene, hydrogen and catalyst were continuously supplied to a Vessel-type 300L polymerization reactor equipped with a stirrer. The polymerization pressure was 0.5 MPa. The polymerization temperature was maintained at 85 ° C. by jacket cooling. Hexane was kept at 25 ° C. and supplied from the side surface of the polymerizer at 40 L / hr. The solid catalyst component [A] and triisobutylaluminum and diisobutylaluminum hydride (9: 1 mixture) were used as co-catalysts. The solid catalyst component [A] was added at a rate of 0.2 g / hr from the middle of the liquid surface and the bottom of the polymer, and triisobutylaluminum was added at a rate of 10 mmol / hr from the middle of the liquid surface and the bottom of the polymer. .. Since the solid catalyst component [A] and the co-catalyst triisobutylaluminum were added at the same timing using one feed line, they were adjusted so as to come into contact with each other before being charged into the reactor. The production rate of the ethylene polymer was 10 kg / hr. Hydrogen was continuously pumped so that the hydrogen concentration in the gas phase with respect to ethylene was 5.5 mol%. Hydrogen was supplied from the catalyst introduction line in advance for contact with the catalyst, and ethylene was supplied from the side surface of the polymerizer. The catalytic activity was 80,000 g-PE / g-solid catalytic component [A]. The polymer slurry was continuously drawn through a flash drum at a pressure of 0.05 MPa and a temperature of 70 ° C. so that the level of the polymerization reactor was kept constant, and unreacted ethylene and hydrogen were separated.

Next, the polymer slurry was continuously sent to a centrifuge so that the level of the polymerization reactor was kept constant, and the ethylene-based polymer and other solvents and the like were separated. At that time, the content of the solvent and the like with respect to the ethylene polymer was 45% by mass.

The separated ethylene polymer was dried while blowing nitrogen at 85 ° C. In this drying step, steam was sprayed onto the ethylene polymer powder to deactivate the catalyst and co-catalyst. To the obtained ethylene polymer powder, 500 ppm of calcium stearate (manufactured by Dainichi Chemical Co., Ltd., C60) was added, and the mixture was uniformly mixed using a Henschel mixer. An ethylene polymer (B-5) was obtained by removing the obtained ethylene polymer powder that did not pass through the sieve using a sieve having a mesh size of 425 μm. The weight average molecular weight of 200 × 10 ^4.

(Manufacturing method of polyethylene resin composition)
A total of 100 parts by mass of the ethylene-based polymer (A-9) and the ethylene-based polymer (B-5) (75 parts by mass of (A-9), 25 parts by mass of (B-5)), and an antioxidant. Ethylene-based by adding 0.3 parts by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and dry-blending using a tumbler blender. A polymer powder mixture was obtained.
The obtained ethylene-based polymer powder mixture was replaced with nitrogen, and then charged into a twin-screw extruder through a feeder under a nitrogen atmosphere. Furthermore, 65 parts of liquid paraffin (P-350 (trademark) manufactured by Matsumura Petroleum Co., Ltd.) is injected into the extruder by side feed, kneaded at 200 ° C., extruded from the T-die installed at the tip of the extruder, and then immediately. It was cooled and solidified with a cast roll cooled to 25 ° C. to form a gel-like sheet having a thickness of 1500 μm.
This gel-like sheet was stretched 7 × 7 times at 120 ° C. using a simultaneous biaxial stretching machine to obtain a stretched film, and the stretched film was immersed in methylene chloride to extract and remove liquid paraffin, and then dried.
Next, it was re-stretched 1.2 × 1.2 times and then heat-treated to obtain a polyethylene resin composition in the form of a microporous film. The measurement and evaluation results are shown in Table 2.

[Comparative Example 2]
(Polymerization step of ethylene polymer (A-10))
In the polymerization step, ethylene was not dissolved in hexane, the hydrogen concentration with respect to vapor phase ethylene was adjusted to 46 mol%, 1-butene was introduced from the vapor phase with respect to ethylene from 15 mol%, and the feed line velocity of the catalyst was 6.0 m. An ethylene-based polymer (A-10) was obtained by the same operation as that of the ethylene-based polymer (A-9) in Comparative Example 1 except that / s was set. The density was 920 kg / m ³ and the MFR was 20 g / 10 min.
Further, as the microporous film of Comparative Example 2, an ethylene-based polymer (A-10) and the ethylene-based polymer (B-5) were used, and 75 parts by mass of the ethylene-based polymer (A-10) and an ethylene-based polymer were used. A microporous film-like polyethylene resin composition was obtained by the same operation as in Comparative Example 1 except that the total amount was 100 parts by mass of 25 parts by mass of the polymer (B-5). The measurement and evaluation results are shown in Table 2.

[Comparative Example 3]
(Polymerization step of ethylene polymer (A-11))
In the polymerization step, ethylene is not dissolved in hexane, the hydrogen concentration with respect to vapor phase ethylene is adjusted to 46 mol%, 1-butene is introduced from the vapor phase with respect to ethylene from 15 mol%, and the catalyst temperature is set to 3 ° C. An ethylene-based polymer (A-11) was obtained by the same operation as that of the ethylene-based polymer (A-9) in Comparative Example 1 except that the feed line velocity was set to 2.0 m / s. The density was 920 kg / m ³ and the MFR was 20 g / 10 min.
(Polymerization step of ethylene polymer (B-6))
Similar to the ethylene polymer (B-5) in Comparative Example 1 except that the polymerization temperature was adjusted to 90 ° C. and 1-butene was introduced from a 0.1 mol% vapor phase with respect to ethylene in the polymerization step. An ethylene polymer (B-6) was obtained by the above operation. The weight average molecular weight of 20 × 10 ^4. Further, as the microporous film of Comparative Example 3, an ethylene-based polymer (A-11) and an ethylene-based polymer (B-6) were used, and 75 parts by mass of the ethylene-based polymer (A-11) and the ethylene-based polymer were used. (B-6) A microporous film-like polyethylene resin composition was obtained by the same operation as in Comparative Example 1 except that the total amount was 100 parts by mass of 25 parts. The measurement and evaluation results are shown in Table 2.

[Comparative Example 4]
(Polymerization step of ethylene polymer (A-12))
In Comparative Example 1, except that ethylene was not dissolved in hexane, the catalyst temperature was set to 3 ° C., the feed linear velocity was 2.0 m / s, and all the catalyst / ethylene / hexane were simultaneously fed in the polymerization step. The ethylene-based polymer (A-12) was obtained by the same operation as that of the ethylene-based polymer (A-9). The density was 947 kg / m ³ and the MFR was 10 g / 10 min.
(Polymerization step of ethylene polymer (B-7))
An ethylene-based polymer (B-7) was obtained by the same operation as that of the ethylene-based polymer (B-5) in Comparative Example 1 except that the polymerization temperature was adjusted to 70 ° C. in the polymerization step. The weight average molecular weight of 400 × 10 ^4. Further, as the microporous film of Comparative Example 4, an ethylene-based polymer (A-12) and an ethylene-based polymer (B-7) were used, and 75 parts by mass of the ethylene-based polymer (A-12) and the ethylene-based polymer were used. (B-7) A microporous film-like polyethylene resin composition was obtained by the same operation as in Comparative Example 1 except that the total amount was 100 parts by mass of 25 parts. The measurement and evaluation results are shown in Table 2.

[Comparative Example 5]
(Polymerization step of ethylene polymer (A-13))
In the polymerization step, the hydrogen concentration with respect to vapor phase ethylene was adjusted to 48 mol%, 1-butene was introduced from the vapor phase at 2 mol% with respect to ethylene, the catalyst temperature was set to 3 ° C., and the feed linear velocity was 2.0 m /. The ethylene-based polymer (A-13) was obtained by the same operation as that of the ethylene-based polymer (A-9) in Comparative Example 1 except that the temperature of the ethylene-dissolved hexane was set to 3 ° C. .. The density was 947 kg / m ³ and the MFR was 10 g / 10 min.
Further, as the microporous film of Comparative Example 5, an ethylene-based polymer (A-13) and an ethylene-based polymer (B-5) were used, and 75 parts by mass of the ethylene-based polymer (A-13) and the ethylene-based polymer were used. (B-5) A microporous film-like polyethylene resin composition was obtained by the same operation as in Comparative Example 1 except that the total amount was 100 parts by mass of 25 parts. The measurement and evaluation results are shown in Table 2.

The polyethylene composition of the present invention is particularly useful as a raw material for a separator because it can impart excellent strength and fuse performance when processed into a separator and has good slit processability.

Claims (12)

The weight average molecular weight (Mw) is 100,000 or more and 1,000,000 or less.
A polyethylene resin composition having a molecular weight distribution (Mw / Mn) of 2 or more and 18 or less.
In a solution using o-dichlorobenzene as a solvent, which is an extract component obtained by temperature-increasing free fractionation according to "Temperature-increasing free fractionation condition of polyethylene resin composition" in the following (Condition 1), the following (Condition 1) When cross-separated chromatography measurement was performed according to "CFC measurement conditions for extracted components" in
The integrated elution amount of 40 ° C. or higher and lower than 90 ° C. is 10% by mass or more and less than 70% by mass of the total elution amount.
The integrated elution amount of 90 ° C. or higher and 95 ° C. or lower is 10% by mass or more of the total elution amount.
The temperature at which the maximum elution amount is 88 ° C or higher and 100 ° C or lower.
Polyethylene resin composition.
(Condition 1)
"Temperature rise free separation condition of polyethylene resin composition"
(1) Solvent; Toluene (2) Socksley extraction time; 6 hours (3) Method of collecting the extracted components extracted in the toluene solvent; Methanol is poured into the toluene solvent for reprecipitation, and the extracted components are suction-filtered. To get.
"CFC measurement conditions for extracted components"
(1) The o-dichlorobenzene solution of the extracted component is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the extract component is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (d) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 69 ° C. at 3 ° C. intervals.
(C) The temperature is raised from 69 ° C. to 100 ° C. at 1 ° C. intervals.
(D) The temperature is raised from 100 ° C. to 120 ° C. at 10 ° C. intervals. The comonomer content when the extracted component obtained by temperature-increasing free separation of the polyethylene resin composition according to the "temperature-increasing free separation condition of the polyethylene resin composition" in the above (Condition 1) was measured by 13C-NMR. Is 0.01 mol% or more and 5 mol% or less,
The polyethylene resin composition according to claim 1. The melting point of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 125 ° C. or higher and 135 ° C. or lower. ,
The polyethylene resin composition according to claim 1 or 2. The lamella thickness of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 6 nm or more and 14 nm or less.
The polyethylene resin composition according to any one of claims 1 to 3. The lamella thickness of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is determined.
10 nm or more and 14 nm or less,
The polyethylene resin composition according to any one of claims 1 to 4. The weight average molecular weight (Mw) of the extracted component obtained by subjecting the polyethylene resin composition to the temperature-increasing free fractionation according to the "temperature-increasing free fractionation condition of the polyethylene resin composition" in (Condition 1) is 20,000. 350,000 or less, and the molecular weight distribution (Mw / Mn) is 2 or more and 14 or less.
The polyethylene resin composition according to any one of claims 1 to 5. A solution using о-dichlorobenzene as a solvent, which is an extract component obtained by separating the polyethylene resin composition by increasing the temperature according to the “conditions for separating the polyethylene resin composition by increasing the temperature” in the above (Condition 1). In CFC measurement according to the above-mentioned (Condition 1) "CFC measurement condition of extracted component",
The temperature at which the integrated elution amount reaches 10% by mass of the total elution amount is 70 ° C. or higher and 90 ° C. or lower.
The polyethylene resin composition according to any one of claims 1 to 6. The Ti content of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 5 ppm or less.
The polyethylene resin composition according to any one of claims 1 to 7. The Al content of the extracted component obtained by separating the polyethylene resin composition by increasing the temperature according to the "conditions for separating the polyethylene resin composition by increasing the temperature" in the above (Condition 1) is 10 ppm or less.
The polyethylene resin composition according to any one of claims 1 to 8. In a solution using o-dichlorobenzene of the polyethylene resin composition as a solvent, when CFC measurement was performed in accordance with the following conditions (Condition 2),
The integrated elution amount of 40 ° C. or higher and lower than 95 ° C. is 15% by mass or more and 70% by mass or less of the total elution amount.
The integrated elution amount of 95 ° C. or higher and 105 ° C. or lower is 15% by mass or more of the total elution amount.
It has at least two or more elution peaks, and the temperature at which the maximum elution amount is 88 ° C. or higher and 100 ° C. or lower.
The polyethylene resin composition according to any one of claims 1 to 9.
(Condition 2)
(1) The o-dichlorobenzene solution of the polyethylene resin composition is held at 140 ° C. for 120 minutes.
(2) The o-dichlorobenzene solution of the polyethylene resin composition is cooled to 40 ° C. at 0.5 ° C./min and then held for 20 minutes.
(3) The temperature of the column is raised at a rate of 20 ° C./min by the temperature program shown in (a) to (e) below. Hold that temperature for 21 minutes at each temperature reached.
(A) The temperature is raised from 40 ° C. to 60 ° C. at 10 ° C. intervals.
(B) The temperature is raised from 60 ° C. to 75 ° C. at 5 ° C. intervals.
(C) The temperature is raised from 75 ° C. to 90 ° C. at 3 ° C. intervals.
(D) The temperature is raised from 90 ° C. to 110 ° C. at 1 ° C. intervals.
(E) The temperature is raised from 110 ° C. to 120 ° C. at 5 ° C. intervals. The Ti content of the polyethylene resin composition is 5 ppm or less.
The polyethylene resin composition according to any one of claims 1 to 10. The Al content of the polyethylene resin composition is 10 ppm or less.
The polyethylene resin composition according to any one of claims 1 to 11.

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